A heavy duty transit van carrying half a million pounds in used notes is high jacked, drivers and all, and SI 10 is tasked with finding it. Meanwhile, Spikings has his hands full trying to get Dempsey to part with his gun, as it is illegal for police officers in England to carry one.

Dempsey takes the place of American hit-man Schwartz to infiltrate a gang of drug dealers who are lacing T-shirts with heroin. Little does he suspect that their main contact, Lei Shan carries a grudge against the real Schwartz. When Makepeace gets her hands on one of the T-shirts via one of her contacts, the undercover Dempsey finds himself forced to bump her off.

Jailbird Charlie Wilson wants to speak to Gordon Spikings alone concerning an urgent matter. But he shuts up tight after his little boy is kidnapped in the park. Meanwhile Spikings finds himself subject to a bombed briefcase while traveling by tube.

Makepeace has been asked by her best friend, Sarah Hackett, to be the matron of honour at Sarah's wedding. Makepeace accepts. Makepeace is giving Sarah a lift to the railway station. Sarah is off to Harrod's with her father, Sir Lionel Hackett, who turns out to be a judge. Sarah is murdered while she is on the train. Makepeace is devestated when she is informed.

Sir Lionel, however, takes the law into his own hands. Makepeace gives Sir Lionel a photo-fit of a man who was seen at the railway station where Makepeace had taken Sarah. Sir Lionel assumed that he was the killer and goes in search of him. But, what Sir Lionel doesn't know is that he is looking for the wrong man.