Ann (Arrested Development)
The fact that Mae Whitman played Ann in Arrested Development instead of the character’s original actress Alessandra Torresani is the finest part of the change. To keep you on your toes, they originally planned to constantly switching around the actress who played Ann, according to Mae, who spoke to People TV. Then they persisted with me, which I consider to be a true insult. “No, no, you’re making the whole unmemorable thing work, let’s just go with that,” they said.
Carol (Friends)
RIGHT?! Anita Barone played Carol for just *one* episode, but it was a crucial scene because Ross learned he was going to become a father there. In the end, Anita decided against continuing the show in order to pursue additional full-time acting roles (RIP, Friends residual checks), thus Jane Sibbett was cast in her place.