Phantom of the Roller Coaster: Part 1 - S3-E23
Other mistake: The amusement park is called Fun Universe, but the pendant on the wall is misspelled as 'Univers'.
The Richest Man in the World - S3-E17
Other mistake: When Wonder Woman chases the guy in the factory, all of the scenes of her jumping plus the last scene of the guy running away and her jumping on top of him are reused from S2E17.
The Starships Are Coming - S3-E15
Other mistake: The images of the UFOs shooting are reused from S3E13.
My Teenage Idol Is Missing - S3-E1
Other mistake: During the first concert, a man and a woman stare at the camera and greet.






Answer: The first actress, Cloris Leachman appeared in the TV movie which ended up being the pilot for the series. At the time, Leachman was already starring in her own TV series "Phyllis" (a spin off her role in "The Mary Tyler Moore Show"). This was actually the 2nd TV movie meant to be a pilot and the first one wasn't picked up. It's likely she thought the show would be picked up. After season 1, in which Carolyn Jones played the role, ABC was slow to make a decision to pick up the series for season 2 and CBS picked up the series. When CBS picked up the series, they changed the time setting of the show and replaced all the actors, with the exception of Carter and Waggoner (with Waggoner playing a different role technically), resulting in Beatrice Straight being cast.
Bishop73