Dirk's client David Edwards is found dead after claiming that the Pentagon are out to kill him. His widow hires Dirk to catch the murderer, telling him that her husband was working on top secret computer software which could spell danger if it fell into the wrong hands. Dirk believes there is a connection with his other client, Emma Reynolds' philandering husband Oliver, obsessed with the fact that his horoscopes keep coming true. Having shown that the horoscopes are a fraud Dirk sets out to find the real reason for Edwards' murder.

Dirk is in the frame when two of his former clients are killed and plans to skip the country though he is waylaid when Melinda Fulstone asks him to identify her stalker - actually Dirk himself conducting an experiment. Dirk believes the murderer is Robbie Glover, whom he accidentally had convicted for killing his own brother - particularly when Robbie tries to strangle him. But soon Dirk works out that Robbie has been framed and that there is somebody nearer home with a grievance against him.