So as not to "spoil" anything, the plot is as follows: A group of young people get stranded in the middle of nowhere and trouble ensues.
This movie has a plethora of similarities to the recent remake of "The Hills Have Eyes". The only redeeming quality this movie has is a bevy of good looking 19 year-old girls. I'm a straight woman, yet even I couldn't tear my eyes away from the numerous shots of these tanned, leggy girls with their flat abs, perfectly round, er. curves, and cellulite-free thighs. It was like watching a Bally's Fitness commercial.
So much for the good.
Other than providing nothing new in the way of story or effects, the movie manages to annoy more than entertain, unless you want to watch it MST3K-style and mock it aloud in your living room with your friends over a case of beer (because that's about how much beer you'll need to numb the pain).
It's really hard to tell one gorgeous chick from the next, but there were some memorable male characters. Notice I said "memorable" -- not "good".
The first was the guy at the gas station. He looks strikingly like Hugh Laurie from the excellent Fox series, "House".
Amongst the youngsters in the doomed RV is a guy who was spawned from both Vanilla Ice and Eminem. The 2 minute joke of a pretty white boy talking like a gansta in the hood got old after...well, 2 minutes. Then it was just embarrassing. Although it's not the actor's fault, I want to blame him anyway. "Words" such as "yo", "aww-ite" and "dog" interspersed with the usual expletives went from satirical to just plain offensive.
I don't know the budget of either this film or "The Hills Have Eyes" (2006), but either could have been made for $3M or less. It would be amusing to watch them back to back so you can see the amazing similarities -- both have motor homes, both use unfamiliar faces, both have cunning and creepy foes, and both take place in the middle of nowhere.
This film was made several years before "Hills" and I never saw the original, so I cannot compare. But comparing to the remake of "Hills", there are myriad similarities but only one difference: One works and one doesn't. And "Detour" just doesn't work.
I gave it a 5/10 for the good-looking women.