UFO - Season 1 - Eps 15: Flight Path
A SHADO Technician, who is being blackmailed for information by an unknown party, is caught by Freeman, but not before the information is passed. The Technician, Paul Roper, divulges what information he gave to the blackmailers, to SHADO. After much work on the cryptic data, they discover it is part of a plan by the aliens to attack the Moonbase in a way that would be undetectable. Now it's up to Roper to redeem himself, as he is sent on the suicide mission to stop the attack. If he fails, the base will surely be destroyed.
About UFO

Title: UFO
First Air Date: 1970-09-16
Last Air Date: 1973-03-15
Status: Ended
Rating: 7.6/10 (from 45 votes)
Language: EN
Seasons: 2
Total Episodes: 26
Network: Associated Television
Genres: Sci-Fi & Fantasy, Drama, Action & Adventure
Production Companies: Century 21 Television, ITC Entertainment
Synopsis
A secret, high-technology international agency called SHADO defends Earth from alien invaders.
Cast

Ed Bishop
Cmdr. Ed Straker