In the late 1960s, three Harvard students Jessica, Leo and Nick grow close as they undergo personal changes, but their friendship is jeopardized by romantic feelings both men develop for Jessica.

At Melbourne's Russell Street Police Headquarters, Sgt. "Bluey" Hills, unable to work within the existing police squads, oversees Department B. They're assigned cases other departments could not readily solve by conventional means, with Hills applying his unconventional methods to bring about their resolution. Bluey's investigations are supported by newly assigned Gary Dawson, long-time cohort Monica Rourke, and undercover officer Reg Truscott, who spends his time ostensibly working as a small-time burglar, and supplying Bluey with information on the activities of local criminals.

When the clubhouse of a group of country kids, known as the "Terrible ten" needs money for funding they invent numerous ways to make money. During their attempts at making puddings and selling mineral water they stumble on a formula for breeding coloured sheep.