REGULAR CAST:

William Shatner as Captain James T. Kirk
Leonard Nimoy as Spock
DeForest Kelley as Dr. Leonard H. McCoy
James Doohan as Chief Engineer Montgomery 'Scotty' Scott
George Takei as Lieutenant Hikaru Sulu
Walter Koenig as Ensign Pavel Andreivich Chekov
Nichelle Nichols as Lieutenant Uhura
Majel Barrett as Nurse Christine Chapel

GUEST CAST:

Bobby Bass as Chekov's Helper in Mirror Universe
Bob Clark as Chekov's Helper in Mirror Universe
Pete Kellett as Farrell
Barbara Luna as Lt. Marlena Moreau
Eddie Paskey as Lt. Leslie (uncredited)
Vic Perrin as Tharn
Garth Pillsbury as Wilson
John Winston as Lt. Kyle/voice of Computer

PRODUCTION:

WRITER: Jerome Bixby
DIRECTOR: Marc Daniels