Much like Jodie Foster's Flightplan, Wind Chill is an example of a 'first hour' movie. The first hour, played alone, would make for an intriguing and suspenseful short film, with Emily Blunt and Ashton Holmes starring as two unnamed characters, college students who don't know each other but agree to share a car because they both need to travel the snowbound roads to Delaware. Because of the odd things he says and the questions he avoids during the trip, the girl begins to suspect that the boy is not who he says he is, and she starts to question why he seems intent on getting off the main highway and taking the back roads. Eventually, their car will end up swerving off the road and barreling into a snow drift, which is exactly the point when you should get up and leave the theater. Just leave the rest of it to your imagination, because what really happens next is not only stupid, it's also complicated-stupid -- a few innocuous boo-moments that require an entire confusing, extraneous backstory to give them some plausibility.
The only way to make Wind Chill interesting is to examine it the way a lot of people in Hollywood are going to -- as an opportunity to scrutinize the star-potential of Emily Blunt. After practically upstaging star Anne Hathaway in The Devil Wears Prada with only a small supporting role, Blunt began to be compared to a young Kate Winslet and was put on a fast-track; she has since inked deals to appear in the big-budget Julia Roberts-Tom Hanks drama Charlie Wilson's War and to play young Queen Victoria in the Scorsese-produced biopic, among other projects. The stage is almost entirely hers in Wind Chill, and she certainly does hold her own, giving an entirely full-throated, aggressive performance as the antsy college student, and even remaining committed and engaged in the role after the plot turns into a morass of stupidity. Like an actor working off a green-screen, there are moments in Wind Chill where Blunt has to act like she's facing some terrifying special effects, and she plays up her horrified reactions appropriately.