text: Liana (Katie Saylor): "Daughter of an Atlantean father and an extraterrestrial mother". The beautiful blonde Liana possessed greater than human physical strength due to her mother being from a planet with a higher gravity than Earth. (However, not much use was ever actually made of Liana's strength.) She also had powerful psychic abilities (presumably due to her mixed heritage) which allow her to, among other things, telepathically communicate with animals - especially her cat Sil-El. Saylor left the show after the episode "Turnabout" due to illness. In the next episode "Riddles" the reason for her not being present with the group was given that she opted to stay a few days at Coriel to help the inhabitants work out their new government and would catch up with the group later.
  Dr. Jonathan Willoway (Roddy McDowall): "Rebel scientist from the 1960s" who has a mastery of computers, robotics and scientific knowledge which is quite useful to the group. He is something of a never-entirely-trustworthy black sheep, not unlike Doctor Smith from Lost in Space but without the latter's cowardice; he often tends to do things for his own mysterious reasons. Over the course of the episodes, however, the black-clad Willoway comes to care about Scott and his fellow travelers and becomes more integrated into the group, although Fred makes no secret about still not trusting him, which leads to a bickering Spock/McCoy-style relationship between the two.
  Sil-El (The Felix Team): Liana's companion and pet, a "tuxedo cat" with which she can communicate telepathically and who sometimes scouts ahead for her, acting as an extra set of eyes and ears.