...and soon enough, like any situation where the pressure does nothing but build, it'll explode.
Chow Yun-Fat plays Chung Tin Ching, a prisoner on a manslaughter charge, who befriends a harmless, naive twig of a man named Yiu, also on a manslaughter term. At first, he's a nuisance, but as he sees just how useless Yiu is in his situation, he can't help but step in when Yiu's blunders aggravates the wrong people. Friendship blossoms, and then the two of them must fend for themselves and each other against the cruel warden, Officer Hung, and Hung's obnoxious rat. The situation intensifies... it escalates... and when it finally explodes, it is intense, emotional, and effective.
I've seen six of Ringo Lam's films now, the other four being Prison on Fire II (right after I saw this one), City on Fire, Full Contact, and two of his Van Damme vehicles, and Prison on Fire is definitely the second-best film I've seen from him so far. It's nothing original, and the villains are a little cartoonish at times, but for the most part, it's a great movie, and definitely among the best of Chow and Lam.