Lennox is tasked with assisting Webb and Holmes on a drugs bust, but after meeting with an old friend, who is a well-known figure in the Scottish parliament, he is more concerned with carrying out an unofficial investigation into a possible blackmail racket. When one of the suspects in the drugs bust manages to get away, Meadows and Webb are left furious. However, when Lennox explains to Meadows that he is acting on behalf of a friend, to the consternation of his colleagues, Meadows offers him support to investigate the detective agency involved in the blackmail scam, much to Webb's dismay. Lennox enlists Hagen to help out on an obbo.
