The Big Bang Theory star Jim Parsons has revealed that he fought to keep Mayim Bialik as a series regular on the show.

In The Big Bang Theory: The Definitive, Inside Story of the Epic Hit Series by Jessica Radloff, a series of interviews with cast and crew members, Parsons said he was worried that Amy was being written off the show in season four (via Entertainment Weekly). “At some point in season four – I don’t know if something caused it or not – I remember saying to Todd, ‘I will not let this character go without a fight,’” he recalled.

Parsons felt so strongly about his on-screen love interest remaining in the series that he preempted a talk with showrunners should they decide to write her off. “But at some point I felt a certain way about working with Mayim that I was like, if for whatever reason we seemed to be weaning her off of this show as a character, I would go and talk to them. “That was notable for me, only in that I almost never disagreed with the writers,” he added.

The Sheldon actor also revealed how writers had “no choice but to evolve the character” of Amy, who was initially intended as a female version of Sheldon. He called the decision to introduce her “one of the smartest things that the writers room ever did”. Bialik herself was unsure about Amy’s future and thought she might only appear in one episode in season three. “After my episode in the season three finale, I literally thought my character might never come back. I had been out of the industry for so long… it really could have gone either way,” explained Bialik.