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Colony In Space: Episode Four (HHH4)
Last updated 18 June 2023
8:30pm-9:00pm EDT (00:30 GMT) < > « »
Retro TV
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Featuring: Jon Pertwee, Katy Manning, Tony Caunter, Roger Delgado, Bernard Kay, Morris Perry, John Ringham, Helen Worth
The Doctor discovers a doomsday machine left by a highly advanced civilization.
Synopsis Source: Retro listings
Broadcast Source: Retro TV