Guest Stars James Doohan as Lt. Cmdr. Montgomery "Scotty" Scott Nichelle Nichols as Lt. Nyota Uhura George Takei as Lt. Hikaru Sulu Walter Koenig as Ensign Pavel Chekov Majel Barrett Roddenberry as Nurse Christine Chapel Marj Dusay as Kara Sheila Leighton as Luma James Daris as Creature