Guest Stars DeForest Kelley as Dr. Leonard Horatio "Bones" McCoy James Doohan as Lt. Cmdr. Montgomery "Scotty" Scott Ken Lynch as Vanderberg Barry Russo as Lt. Cmdr. Giotto Brad Weston as Appel Biff Elliot as Schmitter George E. Allen as Engineer #1 Jon Cavett as Guard Uncredited Janos Prohaska as The Horta