We mentioned having seen Free Birds, the animated romp in which two turkeys travel to Plymouth Rock to attempt to save the entirety of the turkey population by removing themselves from the menu.  The movie is enjoyable, certainly not a turkey itself, but definitely a time travel disaster.

Let this be a spoiler alert:  the entire plot is about to unravel into this article.  If you have not seen the movie, you might enjoy it a bit more if you watch it before you read this.  On the other hand, it is probably good enough to be worth watching even if you know its secrets in advance.  You have been alerted.

It begins with two turkeys, Reggie an intelligent nerdy misfit who has been trying to warn the other idiot barnyard turkeys that the farmers do not love them and ultimately will kill them all and eat them.  He stumbles into the unusual fate of being the pardoned turkey who then becomes playmate of the daughter of the President of the United States.  He quickly learns how to order pizza and bill it to the White House, and becomes friends, of a sort, with the delivery boy.  The other, Jake, was a chick whose mother managed to smuggle him out of the poultry production factory, but who could not save the eggs she gave him.  As he is feeling miserable about this, someone appears from the sky, introducing himself as The Great Turkey, and sends him on an elaborate mission that begins with kidnapping the pardoned turkey and then stealing a secret government time machine to complete the previously mentioned mission.  He is given a "special" doorknob that is supposed to protect him.  Somehow along the way he grows into a brave and strong adult turkey with, as he himself says, nothing in his head.

Again through a comedy of errors they succeed in getting aboard the time machine, called S.T.E.V.E., and arrive in the past.  They immediately meet the local turkeys, the misfit turkey falling in love with Jenny, a hen who is a bit of an odd bird herself but happens to be daughter of the Chief Broadbeak.  (Turkey society has much in common with the Native Americans, but then, in a sense they are that.)  They are staying one step ahead of the evil Myles Standish, who has promised Governor Bradford that there will be turkeys for his upcoming feast with the local indians but cannot seem to deliver.  He shows Jenny the time machine, but as much as she likes him, she is determined to save her flock.  Reggie agrees to help.

Unfortunately, working with Jake brings disaster, as Standish finds the hidden nest and captures a large number of birds, which are caged back at the town.  Broadbeak is killed in the attack (but not taken), and then it is found that Jenny, not her brother, was her father's choice to replace him.  A dejected Reggie takes the time machine back to the future.

He arrives early, and opening a door he encounters himself, slams the door, and winds up with the doorknob in his hand.  He then has discussions with three versions of himself who chose to pop in from the future to talk to him about it, until S.T.E.V.E. clarifies it all, that Reggie is The Great Turkey.  Steve and Reggie find the young Jake, make the pronouncement (with appropriate special effects), and give Jake the doorknob.  But in the past, Jake and Jenny are preparing to lead the turkeys against the fort, which is preparing to defend itself with cannons.

Reggie and S.T.E.V.E. appear just in time to stop the cannonfire, and then with S.T.E.V.E. translating (the birds can talk to the ship, but people can't understand them) he introduces pizza to the pilgrims and the indians, the pizza delivery boy bringing stacks of boxes from the ship to feed everyone.  Thanksgiving is born, and the turkeys are all released unharmed to share the pizza.  Reggie stays in the past with Jenny, while Jake boards S.T.E.V.E. intending to be some kind of superhero through time and space.

Glaring problems:

• If they have changed history so that turkeys are not on the menu, how do they know that turkeys were ever on the menu so that they can change it?
• If at the end Reggie stays in the past and Jake takes the time machine, how do Reggie's future selves come back to visit him?
• If Reggie became The Great Turkey that launched the mission because he had been on the mission, how did the mission get started originally?
• If for generations turkeys have not been raised, killed, and eaten, how does it happen that Reggie and Jake were actually born in this altered universe?

The story begins when Jake and Reggie, two turkeys, steal a secret government time machine intending to travel to Plymouth Rock, 1621, to save all of turkeydom from becoming the featured menu item at Thanksgiving.  No, it cannot begin there, because before that The Great Turkey has to appear to Jake to give him all the information so he can kidnap Reggie and take him to where the time machine is, so it must begin there.  Wait, though--it turns out that The Great Turkey is Reggie, who traveled from the future after returning from 1621, because he knew that Jake had to go on this mission and take him along.  But Reggie cannot do that, cannot know anything about the mission, until after he travels to 1621 with Jake.

We have a classic predestination paradox, a string of events that support each other but only happen because they happen, what ultimately involves an uncaused cause.  If something only happens because it happens, it does not happen.

The solution to a predestination paradox is to identify an original cause that could have occurred in the original history.  In this case nearly any proposal for such an original cause sounds absurd--but then, the entire movie is absurd, so perhaps we should entertain an absurd original cause.

There are several other problems that will need to be addressed.  The trips we see include Reggie and Jake traveling to 1621, Reggie returning to the present (we will assume 2013), Reggie coming to the present from the future, Reggie coming to the present from the yet further future, Reggie coming to the present from the even yet further future, Reggie traveling back a short time to find Jake, Reggie returning to 1621 with pizza, Jake leaving to fight injustice wherever it occurs in space and time but ultimately reaching the twenty-first century, and Jake returning to 1621.  Not a one of these is without complications.  We shall, however, begin by attempting to imagine an original history that might set up our first trip.

In order for Free Birds to work, there must have been an original cause in the original history that somehow initiated the predestination paradox we see.  There is a lot that has to be accomplished; but we will begin with what we know.

Reggie is the Pardoned Turkey, and is moved to Camp David, where he learns to order pizza delivery.  Jake escapes from a turkey factory, in or near Maryland.  They know nothing of each other.  Meanwhile, the United States is preparing to launch its first chrononaut at a secret base not far from them.

Something must have gone horribly wrong with that trip.

For starters, one of our two turkeys has to become aware of the time machine and know where it is; he also has to get the notion that he could travel to the first Thanksgiving and get turkey off the menu; and he has to be persuaded that the other turkey--of whom he knows nothing at all--is necessary to this excursion.  Those, though, are only the beginning of the complications.

On the surface, Jake seems the better choice.  While it is more difficult to imagine how Jake could become involved with the time machine (Reggie, after all, is already connected to the President), it is plausible that he might have seen Reggie on television--the turkey pardoning ceremony is televised--and gotten it into his dull brain that Reggie is the turkey who can help him.  That, though, leaves us with the problems of The Great Turkey, the Sacred Time Knob, and the promise that he would not give up no matter what.

So we start with Reggie.  The problem here is, why does he connect with Jake?  It's simple enough for him to get the doorknob, even to think of giving it that fancy name--but Reggie is the one who is happy, who has no reason to change history (after all, if there is no Thanksgiving, there is no Pardoned Turkey, and his cushy life is gone).  The idea does not start with Reggie.

It's starting to look as if the idea must start with S.T.E.V.E.--the intelligent time machine itself.  After all, S.T.E.V.E. could have gotten the notion that the turkey pardoning reflects the suffering of an entire race of turkeys, found some poor stupid turkey (Jake) and given him the starting point for the mission.  The recently pardoned and thus media covered Reggie is the perfect choice for a companion, because he is specifically identifiable.  S.T.E.V.E. doesn't need Reggie to pretend to be the Great Turkey.  So S.T.E.V.E. finds Jake, gives Jake the mission including how to find Reggie and where to go to find the time machine, and then waits for them to appear at the base.

Of course, that has us wondering how S.T.E.V.E. got there in the first place.  After all, without the turkeys, S.T.E.V.E. would have launched carrying a chrononaut, who would have given him a test destination, and he would have gone there and back.  What, though, if S.T.E.V.E. launched empty?  The protocol seems to have been that if the launch sequence was compromised the chrononaut should evacuate.  It might be that there was some other interference with the launch, the chrononaut evacuated, and S.T.E.V.E., left to his own devices, decided to change history.  He recruits the turkeys, giving Jake the plan, and their arrival throws the base into an uproar, disrupting whatever the original disruption was and putting the turkeys aboard the time ship.  Jake provides the destination, and the story proceeds from there.

There is of course no Sacred Time Knob.  The entire story is fraught with improbabilities--the timing of events has to be perfect even though it has never happened before, as the turkeys must breach the base, disrupt security, and reach the time machine within a very narrow window of opportunity.  But we deal with improbabilities--we now have a possible scenario that gets the turkeys into the time machine and bound for 1621 to prevent Thanksgiving.

With the perhaps absurd premise that S.T.E.V.E. is the original mastermind of the Thanksgiving plot we have managed to find an original cause for the predestination paradox which sits at the center of the movie.  He takes the turkeys to 1621 and makes them believe it was their idea--or more specifically, makes Reggie believe that Jake believes that it is the idea of a figment of Jake's imagination known as The Great Turkey.  Of course, this version of S.T.E.V.E. was taken before it concocted that plan, so it does not know that it is responsible for it.

Machines being what they are, it seems likely that given the same instruction S.T.E.V.E. would select the same destination, and thus that Reggie and Jake would have the same adventure, meet the same turkeys, and come to the same crisis.  Reggie will return to S.T.E.V.E. and ask to go home.  Then S.T.E.V.E. does something peculiar:  he delivers Reggie to Camp David some time before Reggie left Camp David.  Reggie thus sees his younger self.

He slams the door in the process, so his younger self never sees him; when he does, the doorknob comes off in his hand--and it means nothing to him.  There was no "Sacred Time Knob" in the history he has just seen, because he never took it from the door or gave it to Jake, and S.T.E.V.E. did not have it.  Further, no versions of Reggie are going to come from the future, because he has not yet lived to become his future self (for one reason).  So here is Reggie, having just said goodbye to S.T.E.V.E. (who has not yet left), holding a doorknob and wondering why he has arrived home before he left and what he will do to avoid a serious problem--and let's be clear, if Jake arrives and kidnaps the wrong Reggie, it will be a very serious problem, akin to the watch in Somewhere in Time, except that it will be Reggie who becomes perpetually older (like the character in this comic book story).

This, then, is the critical moment in the story.  As Reggie stands there contemplating the doorknob and talking to no one but S.T.E.V.E. (who does not know that he started this, because when Jake and Reggie took him that future was erased), he must come up with the idea of becoming The Great Turkey, and of imbuing this meaningless doorknob with the imagined power of the Sacred Knob of Time.  He has to do it simply because he realizes he would rather be living with wild turkeys back in 1621 than at Camp David with all the pizza he can eat, because Jenny is there.  He then concocts the plan to find Jake, give him the mission, and get history to repeat itself.

It sounds absurd.  The odds of Reggie kickstarting exactly the same sequence of events are infinitesimal.  Yet this is the only way we get the first part of the movie:  Reggie must replace S.T.E.V.E. as The Great Turkey, and must include the Sacred Knob of Time, and give exactly the same instructions (instructions heard only by the Jake who is in the past) so that a nearly identical history will lead to Reggie returning and finding the doorknob in his hand.

This time he recognizes it as the Sacred Knob of Time, because Jake showed it to him, and so this history stabilizes and time can continue.

There is a bit of a problem arising from the fact that Reggie replaces S.T.E.V.E. as The Great Turkey.  Since Reggie returned before he left, we are inside that first anomaly; in a few hours, S.T.E.V.E. will be launched, and so we are facing the end of this history (whatever happens from that).  The two anomalies interact in complicated ways.

Because Reggie returned early, he is able to leave before S.T.E.V.E. makes his first trip.  That, though, creates a convoluted problem.  Reggie is going to travel back a few days to find Jake, and so replace S.T.E.V.E. in that encounter.  S.T.E.V.E. has, in a temporal sense, not yet left from the future to seek Jake; but in a sequential sense, he already did that, and since the moment of S.T.E.V.E.'s departure has not yet been erased Reggie and S.T.E.V.E. should find that S.T.E.V.E. is already there when they find Jake.  When we reach the moment of S.T.E.V.E.'s departure in this history, Reggie and Jake will be aboard and S.T.E.V.E. will not travel back to become the Great Turkey; but because we have not yet reached that moment we have not yet changed that departure, and so an empty S.T.E.V.E. will arrive to confront Jake, and be there at the same time that Reggie is trying to be the replacement turkey.

Once we reach the moment of departure, though, Reggie and Jake will be aboard S.T.E.V.E., and having already met the Great Turkey Jake will give the destination.  That means that this S.T.E.V.E. will not go find Jake and give him the assignment, and we have an infinity loop, as the presence of the turkeys aboard S.T.E.V.E. prevents S.T.E.V.E. from contacting the turkeys, preventing them from being aboard S.T.E.V.E. and so causing him to contact them.  Since infinity loops prevent time from advancing into the future, if Reggie has not left to find Jake by then he never will.

It thus is obvious that the story fails if Reggie and S.T.E.V.E. leave either before or after S.T.E.V.E.'s original departure time.  However, S.T.E.V.E. is a smart enough machine to recognize both the problem and the solution, and he already knows the launch time (which his actions have not altered).  Therefore S.T.E.V.E. must persuade Reggie to board with the intention of being the Great Turkey for Jake, then depart for the past at exactly the same moment his doppelganger does.  Reggie boards a bit early, perhaps--depending on whether he picks up the pizza now or earlier after finding Jake--but S.T.E.V.E. can as easily hop forward a few hours to the departure time and then make the trip to the past.

By that arrangement, there are turkeys aboard the S.T.E.V.E. being launched from the government facility, so that S.T.E.V.E. does not look for Jake but goes directly to the past, but he is replaced by the other S.T.E.V.E. who leaves from Camp David at the same instant and makes the trip the original S.T.E.V.E. made to find Jake and give him (this time through Reggie) his mission.  All of history is preserved--but for a few quirks that have to be addressed along the way.

To briefly cover four centuries of history as it has been presevered, Jake and Jenny attack the fort without Reggie, the Pilgrims use the cannons, and turkey remains on the Thanksgiving menu.  This raises another serious issue.  All the captured turkeys will be eaten, and most of the rest of the rafter massacred.  Some of these perhaps would have become part of the Thanksgiving feast anyway, but without Jake many more would have escaped and survived.  The probability of both Reggie and Jake being born dwindles.  That has no impact on our present versions--time has not yet reached the moment at which they cease ever to have existed--but it is unlikely in the extreme that Reggie would see himself.  That doppelganger probably does not exist.

There is yet another quirk in this.

The first time Reggie holds the Sacred Knob of Time, that is, from the metaphysical perspective of the first version of history in which he does this, no Reggie doppelgangers can arrive from the future to help him reason through it.  After all, since he is going to change history this cannot be fixed time, and therefore no one can arrive from the future until some version of history has occurred resulting in that future.  Thus for Reggie to come from the future and advise Reggie in the present, Reggie in the present must live to become Reggie in the future and then travel back to this moment.  We again must have an original history devoid of visitors from the future.

That is not normally a problem; other than that it is dangerous to reveal too much of the future to your past self, there is no particular reason why a traveler could not come from the future and alter the original history by appearing in the present.  It is our understanding that the visiting versions of Reggie are simply causing him to do what he is going to do already, and that S.T.E.V.E. has set the timetable for it, so they will not alter anything that matters.  However, we have a serious problem with the notion of Reggie coming from the future, because we do not see a direct route for him to have been in the future.

When Reggie leaves Camp David with S.T.E.V.E., he goes back to find Jake and gives him the doorknob.  Then he travels back to 1621, saves the turkeys, changes Thanksgiving to a pizza party, and stays in the past with Jenny while Jake takes S.T.E.V.E. galavanting through time to right injustice wherever it hides.  Reggie never goes to the future because he stays in the past with Jenny.

In a distinct problem, the versions of Reggie who show up in the future do not seem to have used S.T.E.V.E. or any similar time machine to get there--they simply pop out of the air and are present.  It is as if Reggie has somehow gained the ability to timewalk; either that, or S.T.E.V.E. arrives cloaked, and Reggie appears as he pops out the door, and vanishes as he reenters.  But then, how did he get there at all?

One point to note is that at some point he must have ordered the pizza and picked up the delivery boy.  It may be that after having given Jake his mission Reggie and S.T.E.V.E. returned to this moment intending to order the pizza as soon as the other Reggie departed, and decided to hurry the bird along by interfering.  Of course, he's keeping pretty busy if he makes additional short trips back to overlap himself on this so that there will be three future versions present, and the last one seems to be more delaying than facilitating the trip, but then Reggie might be smart but he's still a turkey.

The other possibility is that Jake returns after years in the future--we know he does, because in the midst of the credits he appears and asks Reggie if he knows anything about the turducken.  If at that moment Reggie gives up his dream of spending his life in the primitive past with Jenny and leaves with Jake, they might possibly travel to a future time when time travel has become common and simple, and Reggie learns to do it without the use of a visible machine.

So the visits from future versions of Reggie to himself are ridiculous, and dangerous in that they might accidentally change important events, but not impossible.

Now Reggie has to launch the next step in the plan.  He has to order pizza--a lot of pizza, but he's having it delivered to Camp David so they'll assume the bill is covered. He has to get the pizza delivery boy to bring all this pizza into the time machine and then take him and it back to 1621.  His arrival must be timed to stop the cannon--but then, as Marty McFly observed, this is a time machine, he can choose his time easily enough.  S.T.E.V.E. will have to translate, both for the delivery boy and for the message when they reach the fort.  He thus stops the fight and saves the turkeys.

And at this point we hit all of the really big problems in the movie.

The first is the obvious infinity loop.  Knowing that turkeys are the main course at Thanksgiving and wanting to change that, Reggie has traveled back nearly four centuries and successfully altered the first Thanksgiving into a pizza party.  It thus seems that he has been successful.  That would mean that turkey has not been on the Thanksgiving menu for the past four hundred years, and Jake and Reggie have no knowledge of a holiday in which turkey is the main course and no motivation to travel Plymouth Colony to change it.  Without their intervention, it is unchanged, turkey is on the menu, and our heroes will make the trip.

On top of this we have a serious genetic problem.  Reggie and Jake are both born on farms which raise turkeys for sale as poultry.  People do eat turkey other than at Thanksgiving, obviously, but the sense of the film is that this is the holiday which supports the industry, and it cannot be argued.  Ultimately the turkey industry is as big as it is because of sales at Thanksgiving.  That means fewer farms and/or smaller farms, and a significant reduction in the probability that either Jake or Reggie will ever be hatched, and correspondingly lower that both will.  This reduction in probability is not merely that their parents might not have been at the same farm, but that given over three centuries in which demand for Thanksgiving poultry has been drastically reduced their great-great-great-great-even-greater-than-that-grandparents are unlikely to have met.  Our turkeys who have eliminated their own motivation for making the trip have also eliminated their own existences.  That does not take into account that Jenny's chicks are probably going to be Reggie's offspring, not those of whatever smart turkey originally won her heart before Reggie intervened (she might originally have been his great-whatever-grandmother), and so we have the shifting of untold turkey matings.

And let us not fail to consider that if there is no Thanksgiving celebration, there is also no pardoned turkey.  It seems a small thing, but there it is.  It is peculiar that Reggie and Jake should exist, given how thoroughly they have undone their own histories.

Some of this we might resolve by that dubious application of Niven's Law, that once Reggie and Jake change the past it remains changed.  This, though, unravels our solution to the Great Turkey Paradox:  if what S.T.E.V.E. did remains done, Reggie cannot replace him.

The ultimate solution concludes that they failed.  It was perhaps a fool's errand from the start--the first Thanksgiving may have served turkey, but it likely also served venison, sea bass, lobster, crab, pork, ham, whatever the colonists and indians had to share with each other.  Already we have a fictionalized version of that meal, created by later minds (Ben Franklin wanted the turkey to be the national bird) and promoted by those raising poultry.  If perhaps the first Thanksgiving was a pizza party, the following year if they had a similar gathering they had neither pizza oven nor time machine, so they ate what they could gather, possibly including turkey.  Jake then snatches Reggie on a futile mission to stop the turducken, and Reggie for whatever reason never returns to Jenny, and history is not significantly different.

After all, if turkey did come off the menu generally, who would think to invent the turducken?

So we can make the time travel story work with a few rather ridiculous assumptions, a lot of improbable coincidences, and an ultimately unsuccessful effort to change the past.  It is still nonsense, even were we to grant turkeys the intelligence to attempt it, but it is a fun family-friendly time travel story.

The movie ends, Jake takes S.T.E.V.E. on adventures to right wrongs throughout timespace, and leaves Reggie in 1621 with Jenny.  Then instantly--but after years for him--Jake returns, concerned about the turducken.  We are not told what happens, but we have a few points that we have to recognize.

That Jake discovered the twenty-first century turducken means that he left Reggie in 1621, where the smarter bird made a life for himself with Jenny, hopefully not becoming a meal for the colonists (now that he no longer has S.T.E.V.E and the pizza delivery boy, whom S.T.E.V.E. must return to the future).  The version of events which we see suggests that Reggie was not there long before Jake returns, but that is a rewritten history--the original history had to extend from here to the invention of the prized creation.

We might note that if the turkeys created an infinity loop Jake cannot have traveled beyond Reggie's departure time.  However, turduckens already existed prior to that departure, and we have already theorized that the mission to remove turkey from the Thanksgiving menu was a failure, so that is not a problem.

There is a potential problem, though, in that Jake seems to be appealing to Reggie for help.  If Reggie gives him advice, the impact on the world is small; if, though, Reggie leaves with Jake to fight the turducken in the future, he erases the entire history created by his presence in the past--Jenny has a different mate, the genetic problem previously addressed is repeated in the opposite direction.

That does not consider the infinity loop that would be created if Jake and Reggie, relying on knowledge of the creation of the turducken, prevent it from being created:  they then would have had no reason to do whatever they did to prevent it, and it would be created, inspiring them to take that action.

Of course, there probably is nothing the intrepid duo can do about this, and perhaps Reggie will recognize it, give Jake some advice, and Jake will do what he does best--apply himself to futile crusades.  As long as he does not fix anything, everything will work.

So now we are finished with the film, again an enjoyable romp despite the temporal problems, most of which might be resolved except for Reggie staying with Jenny in the past.