Practicing to take part in an upcoming pro-am tennis tournament, Magnum is assigned by Robin Masters to protect a spoiled young tennis star who is receiving death threats. Thomas finds his patience tested by the girl's bratty behavior, but is pleased that the tournament sees him reunited with an old flame - who is the girl's main competitor, and thus the prime suspect.

When a doctor who was a nurse during Magnum's days in Vietnam is accused of poisoning patients, he tries to clear her name, but is puzzled by her and her husband's rebuffing his offer of assistance and irritated by an agressive reporter.