Doctor Who , “The Greatest Show In The Galaxy” features Sylvester McCoy as the Doctor and Sophie Aldred as his traveling companion “Ace.” This particular story arc originally aired from December 14th, 1988 to January 4th, 1989, and centers around the Doctor and Ace going to to the planet Segonax to attend the Psychic Circus.
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DVD Review: Doctor Who , "The Greatest Show In The Galaxy"