As everyone else says in their reviews, this film owes a big debt to John Carpenter's Assault on Precinct 13. Well, if you're going to borrow, borrow from the best. So, no, this doesn't score many points for originality, but this taut, stripped down actioner is a thoroughly entertaining film in its own right.

Nikki Amuka-Bird is superb in the main role - as she always is - and lends great depth to the police officer character she plays. All the way through, you feel her fear and tension as the situation spirals out of control, and are fully with her as she fights to survive against the odds.

The action scenes are very well done, and there are enough twists and turns to keep things moving along nicely. Most of the other characters are fairly thinly drawn, but this doesn't really matter, and at around 90 minutes there is no excess flab.

I don't think this set the world on fire when it first came out, but it's a hidden gem of a movie that deserves to be more widely seen. Much better than most bloated blockbusters that cost ten times as much!