In the episode, "Wish Upon A Star", in the first season, John Robinson and Dr. Smith are arguing about getting rid of the thought machine. After Dr. Smith mentions that in the morning he'll go back to the old derelict and he wants to take the robot with him as a servant companion, he goes onto the elevator to go down to the lower deck. He closes the elevator door and before he pushes the button to go down, the elevator is already going down before he pushes the button.