I'll keep this short as a movie like this doesn't deserve a full review.
Given the setting, this movie could have been something really special. It could have been another "28 days later" or even a "Blair Witch Project"
The first 20 or so minutes of the movie I was really excited, directer did a decent job with cinematography and suspense, although I don't think He managed to capture true eeriness of an empty London Underground.
Characters were a big let down. Our "heroine" in this movie is a worthless piece of crap, and you really don't care if she dies or not. As many people have said before, I was rooting for the homeless people and the black guy, who managed to give me a chuckle or two(whether intentional of the writers or not).
The main villain, is kept in the dark for the first half of the movie, but when he is revealed I was really disappointed. I won't spoil it but lets just say my 10 year old sister could probably beat him in a wrestling match.
All in all this is just another mediocre horror film which falls into the trap of following a simple Hollywood formula. This film had a lot of potential but really failed to hit the mark.
Just to highlight how lame this movie was, the characters in this movie had at least FIVE TIMES to finish off and kill the main villain. INSTEAD THEY RUN AWAY.