The Phantom of the Opera star says, "I was sitting in my back yard... and there's this clearing... and there was a mountain lion that came walking through the clearing and was drinking out of my pool.
"I didn't have the fear instinct; I had the New York 'outraged' instinct. I was like, 'What the hell are you doing? Get off my property!' Then I called Animal Control."
Rossum admits the encounter made her realize she's a world away from New York: "We're not in Manhattan any more!"