hint for beginning (major spoilers)

Not just that the Laurie we see in the beginning doesn't teach Yoga in her timeline, but in her timeline, Mike wasn't on the show Roswell.

(Joke) In her timeline, Mike was on Buffy. :)

I agree. It started when she lost contact with Kevin on the phone, and the phone then cracked. That's when she went to a different universe/reality.

She looks a little lost from the start of the party as well. Only just realized why.

Again, that's incorrect. The movie is based on the Schrödinger's cat experiment. The cat only "splits" into two quantum states once it is in the box. In our case, the universe allows for infinite simultaneous states when the characters are "place in the box" when the comet flies overhead.

The idea is that (loosely speaking, I'm not being very rigorous here) for any decision that a character could make, the universe splits into infinite quantum states, each based on a different possible outcome, until it is determined which decision was made.

For instance, if I hold an object in my hand, I can place it on the table in front of me, I can throw it, I can eat it, ... I can do infinitely many things with a given object in my hand. If you are familiar with advanced mathematics, I'd argue that there are uncountably infinite outcomes for any event.

So within the space-time anomaly, anytime a character makes a decision, there would be a different version of that character in a different house who chose another decision. In this house Laurie places down her fork, in this house Laurie raises it up 1 inch, in this house Laurie raises it to her mouth, and so on and so forth.

But that is all besides the point. The movie explicitly states that the past is the same for everyone when the one character announces that he would have cheated on his wife regardless of which "him" is in the room. That's the movie telling you that, not me.

So in conclusion, only choices made within the space-time anomaly can have a different outcome, and there's a house for every one of those outcomes!

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Laurie wasn't a dancer.

The evidence for this is that the main Laurie's character missed out her chance to be the Prima Ballerina for the SF Ballet Troop because she took to long to decide on the understudy role, and Kathryn Maris became the Understudy, who would eventually become the lead after the famous Russian ballerina quit.


In the ending timeline the other Laurie makes a comment "maybe I'll donate to the SF Ballet" and other Lee asks jokingly, "While you're in Vietnam is Kathryn Maris going to understudy your life for you now?". This implies that in the ending timeline Laurie became the Prima Ballerina in the SF Troop and Kathryn Maris is her understudy.

At the beginning of the movie, before the comet, alternative timelines/dimensions/universes absolutely exist----they just don't intersect, so we're only seeing one "regular" timeline/dimension at that point, which is all anyone typically sees, so it doesn't really matter that an infinite number of universes exist generally.

The unique comet situation is what allows the different universes that exist to interact with each other, and cause the problems/weirdness here.

The guy saying he would cheat on his wife in any timeline would be IMPOSSIBLE for him to know for sure, even if it turns out to be true--he is just saying that in his drunken and/or spiteful/antagonistic state, he doesn't have actual knowledge of this--no one does of this sort of thing, it's really just an educated guess.

This is why the character said he used to be on Roswell (something that happened before the comet came) (and incorrect in the "right" timeline), and to help show this, the character who watched Roswell does not recognize him at all, even though his hair was the same on the show and he wasn't just a guest star, etc. Another example is the prior dancing stuff, and a few other past things that were discussed, like the ring and how it came about and how important it was to the character.

The number of universes/realities/timelines is INFINITE--this movie only showed a few, and they were likely all similar due to a small movie budget combined with the fact that it makes it more mysterious/scary/hard to tell which universe a character is in in any given scene, whether its the "right" one or a "wrong" one.

Anyway, If you pay attention, they did NOT have all the exact same outfits or hairstyles in each reality. They just showed a few very similar realities for the purposes of this movie, instead of say, the reality where every person has purple skin or red eyes.