Donald Darko, or Donnie, is an emotionally troubled boy in any event; however, in the timeline we see, someone is playing games with his mind, trying to bring about an outcome that is worse for him than his fate.  There is an original timeline which is if not exactly happy considerably less disturbing than the one in the movie.  From the ending of the movie, we can see that there is another timeline that is also less disturbing than the one we see; in fact, we resolve the story to four timelines, the last being labeled GH, but this one, the AB timeline, worth reconstructing.

In this timeline, nothing and no one comes from the future.  This is an essential element of the time travel theory on this site:  there must be an original history which leads up to the point of departure of any time traveler (including an inanimate one such as a jet engine) before it can depart, and it cannot arrive within the past of that timeline until, in terms of its own sequential existence, it has had the opportunity to depart.  Thus in the AB timeline, Donnie Darko is asleep in bed, hears no voice, and faces no disaster.  The jet engine does not arrive.

Frank does not exist in this history either--that is, the guy in the warped rabbit suit who pushes him to do all kinds of strange things, the first of which is to come out of his room to the golf course.  That also means Donnie doesn't do any of the terrible things we see in the film.  He is seeing a psychiatrist, Dr. Lillian Thurmond, and he did once burn down an empty house, and he certainly has emotional problems for which he is taking medication, but in the film Frank tells him to vandalize the school and to burn down the house of motivational speaker Jim Cunningham.  Without Frank, he doesn't do these things.

It's also worth noting that it was because of the flooding of the school that they had the emergency PTA meeting; and that it was at the emergency PTA meeting that gym teacher and dance coach Kitty Farmer accused English teacher Karen Pomeroy of teaching pornography in the form of a Graeme Greene short story, The Destructors, a story in which children vandalize a house by breaking a water main and then burn down another house.  It is from this incident that Karen Pomeroy is fired roughly one week later; thus, since the school was not vandalized and the meeting not held, there was no reason to fire Miss Pomeroy.  She continues to teach.

However, she does not write cellar door on the blackboard before she leaves, so Donnie does not see it there.

She does introduce Donnie to Gretchen Ross, and their romance won't be too much different than seen, but that he won't abandon her in the theatre to go burn down that house, because Frank's not there to goad him into it.

That also means that the child pornography ring is not uncovered, Cunningham is not discredited, and Kitty Farmer is not required to appear in court to assist his defense.  Thus Mrs. Farmer will fly with the girls to be on Star Search, and not Donnie's mother Rose.  His little sister Samantha will be on that plane, though, when it comes back.

Now it starts to get difficult.  Because Donnie's mother Rose is not on the plane, she's in the house; and that means that when older sister Elizabeth gets accepted to Harvard they don't have the big party.  They probably do have a family celebration of sorts, but not the costume party we see; and certainly Frank is not invited.  Remember, Frank is a real person, apparently a friend of Elizabeth, who wears a sick rabbit costume to the party.  Now there's no party.

This does not impact Gretchen and her mom; Gretchen's mom still vanishes, Gretchen calls the police, she's told to go somewhere safe, so she goes to Donnie's house, where certainly Mom Darko would let her stay (although whatever happened in that upstairs bedroom won't have happened, and there won't be a phone call telling them that the dance team is on its way home).

Yet we now have a problem.  Tomorrow morning near quarter of seven that plane is going to hit that disturbance, and it's going to break up.  One engine from it is going to be thrown back through time twenty eight days, and crash into Donnie's room.  If he's there, he's dead.  The only reason for him not to be there is if Frank lures him out of the room; but Frank can only do this if he's been shot by Donnie already in the future.  So somehow, in the AB timeline, Donnie has to be where Frank is, and has to shoot Frank.  How does this happen?

As crazy as it sounds, there is a way to get there offered by the film.  You have to believe in destiny, or something like that, but it's there.

At some point, while watching football with his father, Donnie starts to see these blurry watery images extending from people's chests telling him where they are about to go.  He also sees one coming from his chest, showing him where he is about to go.  Later he again sees these at the party; by now he's probably mentioned them to his psychiatrist, and is wondering what they are.  There is no party; but then, he might well see that image extending from his chest, or from Gretchens, or possibly from both.

Donnie has not given a thought to time travel, and has not seen nor read the book by Roberta Sparrow, better known in the film and the neighborhood as Grandma Death; he has no reason to think to go there.  However, if this blurry image is destiny and he follows it, he could well wind up at the same place, with the girl, and encounter the burglars.  In the timeline shown in the film, when someone, who turns out to be Gretchen, is approaching him, he puts his face inside the end of the destiny, and sees and hears things within it that he finds disturbing; if indeed there are fragments within that destiny, they might inspire him to leave the house with Gretchen, to see where it is leading.  The other two friends are not here at all this time, because there was no party so they were not at the house.  The fight progresses, the girl is thrown onto the ground, and the car, swerving to avoid good old Grandma Death, runs over the helpless girl.

This would be a most incredible coincidence, perhaps.  After all, we've just suggested that even though there is no party at Darko's house, Frank is still out wearing that rabbit costume and driving the same road.  However, it's not so unlikely as all that.  Frank strikes us as a party guy.  One of the reasons Elizabeth and Donnie thought they could get away with the party was that the town is on the tail end of a four-day "Halloween Festival" at the Middlesex Pavilion Mall.  People are wearing costumes and wandering around as it is.  Somewhere there's going to be another party, and Frank is going to be at it, and he's going to go for beer.  That he's on the same road is not so unusual, since it seems to be out in the boondocks and thus must be the road to somewhere else; if he was headed that way when there was a party at Darko's, there's every reason to think that's where he goes for the beer.  The only remarkable coincidence is that he's at that spot at near enough the same time to run over Gretchen.  Accept that part, and the rest is rather predictable.

Would Donnie have shot him?  Note that he has the gun not because Frank told him to get it but because he followed that destiny thing he could see.  He has not been through as much trouble over the past month, no burnt house, no crashed jet engine, no vandalized school; but perhaps because of this he's a lot closer to Gretchen, and a lot more upset about this.  Even without Frank's toying with him, he's got emotional problems.  He shoots Frank in the eye, and kills him.

The Frank who appears to Donnie in the movie is a ghost--a supernatural being, the spirit of a man who died an unexpectedly violent death.  The ghost has taken advantage of the portal to travel back in time to a moment just before the arrival of the jet engine, and has chosen to do so in order to ruin the life of the person who killed him.  He might even be thinking that if he does it right, Donnie Darko will be incarcerated before the shooting, and he won't be dead.

This timeline isn't quite over.  Although Donnie's mother is home, his sister Samantha is on that plane.  Donnie probably runs, probably with the body of the dead Gretchen, probably in the family car.  His sister is on the plane; the plane hits the vortex, and part of it--plus the Ghost of Frank--travels back four weeks.  The police never catch Donnie, because history has just been altered, and there is no future for this timeline.

The timing of events is not terribly clear despite regular updates on the screen.  There are a couple points at which it doesn't quite match, but these are minor.

In particular, it appears that Donnie is in his bed at midnight at the beginning of October 2, 1988, and that a voice lures him out on a long walk to the golf course.  We could debate whether it's necessarily the case that the jet engine didn't hit the house until after Donnie was asleep on the golf course; what is clear is that he was far enough from it that he didn't hear it happen.  Thus it was after midnight.  At that moment, Frank tells him that the world ends in twenty-eight days, six hours, forty-two minutes, and twelve seconds.

Twenty-eight days later, the clock strikes midnight and we are told that it is October 30, and that there's only six hours to go.  Even if we assume it was only a ten minute walk to the golf course, that's closer to seven hours.  Yet it is a minor point, and accuracy is not a critical factor in this story.

Someone might observe, and correctly, that Donnie doesn't see the strange images that I have chosen to call "destiny" (for lack of a clearer word) until after he has possession of the book in which such images are described.  It's certainly possible that he has already read about those images prior to seeing them; it is equally possible that he has not.

Why does this matter?  If we assume that he cannot see destinies until after he reads about them in the book, then in the AB timeline he could not have seen them.  The sequence of events in the CD timeline (still to come in our analysis, but represented in the film) is that Frank mentions time travel, Donnie asks an unnamed teacher about it, the teacher gives him the book, then he sees destinies.  If reading the book is necessary to seeing destinies, then he can't see them in the AB timeline, and he can't have the gun or go to meet Frank.

Yet whether or not he had already read about them in the CD timeline does not have to be relevant.  He sees them.  His teacher has also read the book, presumably, and, also presumably, does not see destinies.  Apparently some people see them.  In talking to Dr. Thurman, Donnie tells her that he sees these destinies, and has read about them in the book, perhaps implying that after he saw them he read about them.  If so, then the fact that they're discussed in the book is not the cause of him seeing them, and he might well have seen them in the AB timeline, and followed them.

The film shows us the events of the CD timeline.  As it begins, a jet engine has just traveled back through time and is headed for Donnie Darko's bedroom.  If it hits while he's in there, he's dead.  It would be a simple N-jump in that case, as he has nothing to do with the time travel event, so in twenty-eight days the plane will again hit the portal and lose an engine to his bedroom.

Frank interferes.  Being a ghost, he is able to move more quickly than physical objects.  He lures Donnie out of that room and to the golf course far from it in enough time that Donnie is unaware of the crash on his room until the next day.  It's unclear whether he's sleepwalking or following the voice exactly, but either way the ghost saves his life.

He is cognizant of the fact that the ghost saved his life.  Under hypnosis he later tells his psychiatrist that he has to do what Frank says because Frank saved his life.  Frank has nothing but malice for him, and saved him solely to destroy him.

It is in this timeline that all of the events of the movie occur.  Donnie vandalizes his school and burns down Cunningham's house.  The child pornography ring is uncovered, and Rose Darko has to be on the plane with her daughter.  They have the party, and the time travel book is in Donnie's hands, pointing him to Grandma Death when he's trying to figure out what happens.  Again he shoots Frank, and carries the body of the dead Gretchen back to the house, escaping in the car.

At this point, he realizes something of what has happened.  He tells Frank's companion to tell everyone it's going to be O.K.  Perhaps he knows that Frank saved his life to make it worse; he certainly knows that a lot of grief came to a lot of people, including himself, because he was not in his room when that jet engine hit it.  He decides that it would have been better for everyone, and particularly for Gretchen, if he had died in that bedroom.  Thus he somehow takes advantage of the vortex to change history.  He sends himself back to the past, or he sends his decision back to the past.  Whatever he sends, he persuades himself not to leave that bedroom.  This creates the EF timeline.

Normally if you intentionally and successfully change the past, you create an infinity loop, because you now are not in a position to do so.  However, in this case it appears Donnie Darko may have successfully done it without such a problem.

Remember that in the first history, the AB timeline, there was no jet engine and no Frank, and so Donnie was never in any danger, and he didn't act terribly crazy--but he did kill Frank.  That meant that in the CD timeline Frank was around to push him into all the terrible things he hadn't done the first time, but he still killed Frank.  We were very close to an N-jump with a very sad ending when Donnie used the same time travel event to carry his thoughts and intentions back to himself in the past.  Those thoughts must have been to ignore the phantom voice and stay in bed.  Now he dies in his bed.

Because he dies in his bed, doesn't that mean now that he can't send his intents back to himself, instructing himself to stay in bed?  Yes, it does mean that; but now it's not necessary.  In this timeline, Gretchen never meets Donnie; she sits next to some other cute boy in Karen Pomeroy's English class.  Donnie doesn't vandalize the school or burn down the house, because he's already dead.  There will be muted celebration of Elizabeth's acceptance at Harvard, and Samantha will travel to be on Star Search.  Rose will stay home, undoubtedly upset over the loss of her son and not needed to chaperone the girls since Kitty Farmer doesn't have to be at Jim Cunningham's kiddie porn arraignment.  Donnie will not take the gun from the closet, and will not shoot Frank.  Thus Frank is not a ghost; and not being a ghost, he can't take advantage of that portal to go back and play with Donnie.  Further he has no reason to do so.

Thus, at the beginning of the EF timeline, Donnie Darko hears the voice of Frank the Rabbit, but he also feels his own desire, conveyed to him from the future, to ignore it.  He stays in that bed, laughing with the knowledge that the death he's about to meet is better than the misery of the month he would otherwise live, and dies; and in so doing he undoes both the rabbit and the desires.  Both of them having been undone, we must take it once more, to the GH timeline.

In the GH timeline, Donnie Darko is in bed.  No rabbit appears because at the end of the EF timeline Frank was not killed.  No impression to stay where he is comes, but it doesn't matter because there's no reason for him to move.  The airplane engine sails from the future to crash into his bedroom, and he dies.

Because he is dead, the rest of this timeline plays out as the EF timeline did.  In the end, Frank is again not shot, Gretchen Ross is not hit by a car, Karen Pomeroy does not lose her job, Rose Darko is not on the plane, and Jim Cunningham's pornography ring is not exposed.  Well, that, and that the that Samantha Darko is still killed in the plane crash, and that the NTSB's Bill Smith (see Millennium) is trying to figure out how it happened that a boy was killed by a jet engine that fell from a plane that exploded in midair twenty-eight days later on which his little sister happened to be a passenger, those are the sad points of the film.  (What, do you think the NTSB isn't going to realize that the plane that crashed on October thirtieth is missing exactly the same sort of engine that crashed into the house on October second, the origin of which was never discovered?)

The fourth timeline is stable; all causes and effects exist in a single history.  It is not the history we see in the movie; it is the history in which Donnie Darko is killed by a freak accident when the jet engine hits his bedroom while he sleeps.  Time continues.

Frank said that it would be the end of the world; it was not the end of the world.  It was some sort of temporal vortex or portal.  It isn't the end of the world for Frank, who now is not shot.  Donnie's sister Samantha is killed, and the other members of the Sparkle Dancers, along with that crazy gym teacher Kitty Farmer and others on the airplane, but airplane accidents do happen.  Time has not ended; the world may continue, even for Frank.  Was Frank lying?  Let's say he was confused by what had happened.  Since he used the portal to travel to the past, he can't know what happened after the plane crash.  Never having seen such an event before, he guessed it to be the end of the world.  We'll note that he was mistaken about that, even though we don't fully understand the portal itself.

Some will be disappointed.  In order for this film to work, we had to introduce two concepts that are clearly supernatural in some sense:  destiny and ghosts.  I'll take a moment to defend these, not as realities, but as necessary components of the solution to the movie.  That is, if you don't accept them, the movie is impossible; but if you do, the timeline can be unraveled as presented above.

It is clear that Donnie sees those odd ripples of where people are going before he has any reason to expect them.  He has not spoken about time travel to the teacher, and so does not have the book.  Frank has not told him anything about these things.  He sees them.  Now, if they are madness, that's what they are; but they do seem to be presented as working, as showing where someone is going.  The problem with dumping this point is that there does not appear to be any other way to get Donnie to the scene of the crime.  If he does not shoot Frank within a few hours before the crash, he dies, and the movie doesn't happen.  Thus there must be a reason why he is there, and why he shoots Frank, and this is the most plausible.  The alternative is an even more incredible coincidence of some sort.

As to the ghost, it's readily apparent that the wound revealed by Frank in the movie theatre is the wound inflicted on him by the gunshot after the accident that killed Gretchen.  It is also apparent that the gunshot was fatal.  Frank can't be doing this as a living person.  There's no reason to think that the Frank who is alive twenty-eight days before the accident has the power or the knowledge to do the things he does, let alone the motive.  Only the Frank Donnie shot has either the motive or the ability to do this; and only that Frank is stuck for all eternity in that stupid bunny suit, if theories about ghosts are correct.  This has to be the Frank Donnie killed, and therefore he is a ghost from the future.

Now, I don't particularly believe or disbelieve in either ghosts or destiny.  I'd say that ghosts strike me as the more plausible of the two, but both are doubtful enough and difficult enough to prove that it's foolish to pursue argument on the subject.  Don't think I'm arguing for the existence of either.  I'm only claiming that they are necessary for this movie to work as a time travel story.

Is it a time travel story?  In any film as, shall we say, artistic as this, there will be uncertainties.  I have read many interpretations of 12 Monkeys which maintain that that film has nothing to do with time travel.  Like that one, it is entirely possible that this is not a portrayal of real events but of madness.  It is possible that Donnie Darko imagines much of what happens, or does some of it and imagines other parts, that no jet engine hits his house and in the end after shooting someone he collapses into a catatonic state and believes he died four weeks before.  It is as possible that this is a modern telling of Occurrence at Owl Creek Bridge (Ambrose Bierce), a story in which Donnie sees the means of his death break through the roof of his room and in the instant before it crushes him in his bed dreams his escape and all that would flow from it, only to have it end abruptly as the rope tightens around his neck.  In such cases, it doesn't belong on this site at all, as this is about analyzing time travel and time travel movies.  Those who have written to ask about the film apparently think it is a time travel movie, and I have approached it with that assumed.  I'm certainly interested in other interpretations, but if it is a time travel movie, I want to know whether it works.

Given that, it does work, and with less difficulty than I'd anticipated, based on the initial mail.