The one thing that really bothers me about the film is the use of Emile Hirsch and Olivia Thirlby. These are two of the best young actors in Hollywood right now and they're being misused and mistreated in low budget sci-fi horror fare like this? Why? Where are there agents? I'm not really sure that this was a wise career move on either of their parts. Hopefully, we can see both of them move far beyond these types of movies and get back in to dramatic roles that serve them well.
The Darkest Hour was obviously set up for a sequel that we'll never get to see due to extremely poor box office receipts. Hollywood should have learned their lesson the first few times they made this one. While it's not the worst movie, I'd say see it if you're brain is only functioning at half it's normal capacity or you're willing to accept a movie as a mind numbing experience with little to no redeeming quality except for a little bit of fun.
Related article: Speed Racer: You're What's Wrong With America