Lost in Space Wally Cox, Grant Sullivan, Norman Leavitt, Tommy Farrell, Mercedes McCambridge, Lyle Waggoner, Albert Salmi, Royal Dano, Strother Martin, Michael J. Pollard, Byron Morrow, Arte Johnson, Fritz Feld, John Carradine, Al Lewis, Hans Conried, Dennis Patrick, Michael Rennie, Daniel J. Travanti and Michael Conrad. Jonathan Harris, although a permanent cast member, was listed in the opening credits as "Special Guest Star" in every episode of "Lost in Space". Props and monsters were regularly recycled from other Irwin Allen shows. A sea monster outfit that had featured on Voyage to the Bottom of the Sea (TV series) might get a spray paint
Voyage to the Bottom of the Sea (TV series) footage, though several film sequences were removed and had been featured in other first-season episodes such as 'The Village of Guilt' (the giant octopus) and 'Submarine Sunk Here' (the derelict minefield). A few later season two episodes were filmed without Richard Basehart, who was hospitalized for a bleeding ulcer. He filmed the scenes in the Flying Sub for "The Monster's Web" before hospitalization, requiring a stand in and other characters taking over his lines. He was missing entirely from the next two episodes. These episodes didn't feature his character at all, while in one story "The Menfish" Gary Merrill guested