A lethal new drug hits the streets of racially tense Southbridge. With drug crime on the increase, hardened criminal Jacky Chessington changes sides to avenge the death of his friend, agreeing to work undercover. Despite orders, his police liaison, DI Frank Williams distrusts Jacky. Hassim, the city's drug baron, also needs to find the source before it ruins him. Via his association with a brutal building contractor and Docharty, an ex-IRA arsonist and bomb-maker, he discovers Jacky has 'turned' and seeks to use him and then destroy him. Jacky's investigation takes the city to the edge and...