John Abbott guest stars as Sesmar, an alien scientist who has created an android named Raddion (played by the ubiquitous Dawson Palmer). The android is quite a piece of work, seemingly human in every respect save one: he lacks human emotions. To rectify this shortcoming, Sesmar drains the Robinsons of all their emotions and transfers them to his Raddion--leaving only Don (Mark Goddard) "complete" enough to rescue his companions...if he can. ~ Hal Erickson, Rovi