Michael Harvey is mortally ill and his son Ronnie and his girlfriend Susan is preparing a surprise party to celebrate his birthday, which he knows will be his last. During the party Michael Harvey asks Susan to be his wife. Shocked the young woman rushes out of the house and rides away on her bicycle. On her way home she has an accident and nurse Bolton is suspected of causing it, but PC Rowan thinks that something is not quite right, and Susan's bike is missing. Greengrass buys a rare samovar from a family of Russian gypsies, but discovers that there are more "rare" Russian samovars around. PC Rowan is thinking of getting a promotion and wants to take his sergeant's exams.