not horror but dark comedy
There are movies called 'Detention'. At least one is supposed to be awful. This is why it's very important that if you get 'Detention', to watch, that you get the one with Dane Cook. He plays as a supporting cast member.
Thus: if you decide to get 'Detention' only get it if Dane Cook is listed in the cast. This is probably listed as a teen-age movie, which is usually the kiss of death [unless you're a teen-ager]. But this one goes beyond 'teen-age'. examples of this rare movie style are: 'Farris Buller's Day Off' and '10 Things I Hate About You'. Through most of this film it wasn't making any sense; I was left asking: 'Why the heck would I want to watch this!?'
Well, it seemed to have no plot or real story line through about 85% of the movie. At that point somebody said: 'S-*;! The plot and story line aren't here." So then they -kind of- force feed it to their audience. B-U-T, while the plot and story line were failing the film was rather mesmerizing. I would say that there was real good characterization, camera work, and they made the atmosphere visually pleasing. As I'm watching I'm thinking: "This is as stupid as 'Dazed and Confused' or 'Super Bad'." [both not worth seeing] Generally, time travel is a bad idea, too. But in the 'Detention' [with Dane Cook, not the other] there were some wonderful little things, that you'd see in the back ground- and not notice, that would be explained late in the film. IN the end there is no real horror in this film, though there is a lot of dark comedy. I'd say that it should be listed as a comedy- a dark comedy. It felt like it was directed at the philosophy of cliques in high school are mean spirited [not as much as 'Mean Girls' or 'Cruel Intentions'].
*SPOILER ALERT*- In summation: tearing the fabric of time and space is not only bad' but changes to make it right will still have implications on the future; though these changes could be positive implications on the new future. Probably, most of the loose ends were covered in this film. It really is worth seeing and I'm sure that I will watch it several more times in my life- unless I have to go back in time to fix some little problem.