It is London in the 1970s and when assassin Myopic Mick misses his target and kills a vagrant rather than Andy Norris, the hunt for the killer is on. Saved by the texture of the batter on his piece of plaice, Andy (whose only ambitions in life are to seduce his flat-mate Lucy and check out a game of darts from 170) is catapulted into a cat and mouse game to try and apprehend the killer and escaped convict, Kenny 'The Giant' Craft. Hapless PC Crocker, who inadvertently apprehended Craft whilst investigating the theft of a bicycle, leads the search using various ingenious disguises in an attempt to trap the criminals before they can strike again. In a sting operation planned by his bowel-obsessed chief superintendent, a crack team of undercover cops led by Crocker use Norris as the bait in a cunning trap - what could possibly go wrong?