The actress, who left House at the end of its seventh season, revealed that she was tired of her role on the medical drama.
"I loved playing Cuddy for all this time, but I definitely wanted to shift out of that, because I've been playing this sort of repressed control freak for seven years," Edelstein told TV Guide. "I want to have a little bit of fun."
In June, the actress was confirmed for the third season of The Good Wife, playing an intelligent poker-playing lawyer that shares a past with Will Gardner (Josh Charles).
Edelstein went on to confess that she felt anxious about leaving House for The Good Wife.
"When you play the same character for a long time, you have a shorthand. You get onto the set, you put on your outfit and two-thirds of your work is done because you've built on that work for so many years," she said.
Edelstein continued: "When I got this job, I didn't audition for it, so I didn't know what they were thinking in their heads, only what we had talked about on the phone. So it was a risky, scary first day for me and I haven't had that feeling in a long time."
The Good Wife continues to air Sundays at 9/8c on CBS.