'Marineville Traitor' by Alan Fennell

A vital piece of equipment disappears from Marineville Control, and all the clues indicate that Commander Shore is guilty of the crime. Against his will, Troy is forced to place his commanding officer under arrest pending an investigation. However, these events are all part of a cunning plan by Shore, who hopes to trick the real traitor into revealing himself…

Don Mason (Captain Troy Tempest), Robert Easton (Lieutenant George Lee ‘Phones’ Sheridan / Agent X20), Lois Maxwell (Lieutenant Atlanta Shore), Ray Barrett (Commander Sam Shore / Lieutenant Fisher / Titan)

Directed by Desmond Saunders
Produced by Gerry Anderson

TX (UK): 20th June 1965

Notes:
*Featuring Captain Troy Tempest, Lieutenant George Lee 'Phones' Sheridan, Commander Sam Shore, Lieutenant Atlanta Shore, Lieutenant Fisher and Marina