UFO (1970)

S01E15 Flight Path

A SHADO technician named Paul Roper finds himself under the pressure of blackmail from an unknown source. Just as Freeman catches him, Roper manages to reveal the details of the information he shared with the blackmailers to SHADO. Through extensive analysis of the cryptic data, the team uncovers a plot by the aliens to launch a stealth attack on the Moonbase. With the base’s safety hanging in the balance, Roper is tasked with a dangerous mission to thwart the impending assault. If he doesn’t succeed, the Moonbase faces certain destruction.