Turner continues his investigation into the murky world of pimps and prostitution as he investigates crime boss Craig Fenton, whom he suspects is dealing heroin and cocaine through a network of prostitutes. When one of Fenton's prostitutes is beaten within an inch of her life, Turner tries to convince her flat-mate to give evidence against Fenton and reveal the motive behind the attack. Meanwhile, Casper and Bryant deal with a ruckus between the husband of a school teacher and a pupil. Although the husband suspects that his wife has been playing away, Casper subsequently discovers that the teacher is addicted to heroin, and that the pupil in question is in fact her drug dealer.