Kaley Cuoco has admitted she was left horrified after a Botox treatment went wrong during her time filming The Big Bang Theory, revealing the cosmetic procedure temporarily froze her face and affected her performance as Penny.
The actress, now 40, shared the story while appearing on the Not Skinny But Not Fat podcast, explaining the incident happened midway through the long-running CBS sitcom. Excited to try Botox for the first time, Kaley opted for injections in her forehead — a decision she quickly came to regret.
Returning to set, she realised she could no longer move her forehead, a major problem for a character whose comedy relied heavily on facial expressions. Kaley recalled struggling through scenes, delivering jokes while her face remained completely still. “I couldn’t believe how bad it looked,” she admitted.
While she hasn’t sworn off Botox entirely, Kaley now avoids forehead injections altogether, choosing more subtle treatments around her eyes and neck instead.
The actress is set to appear on The Graham Norton Show, where she also revealed that her fiancé, actor Tom Pelphrey, has never seen The Big Bang Theory. Kaley recently teased fans by hinting she may be open to returning as Penny in the upcoming spin-off, Stuart Fails to Save the Universe.