Leslie Mann was a mess when she worked with hero Judi Dench

Leslie Mann was such a mess when she worked with her hero Judi Dench, it took her two hours to "calm down" and film their scene together.

The Knocked Up star partnered with the British Oscar winner in the new film version of Noel Coward's play Blithe Spirit, and really lost the plot when she got up close and personal with the great Dame.

"I was terrified," Leslie told America's Live with Kelly and Ryan. "It's Judi Dench and she's, like, one of my heroes. The first time we worked together, I didn't get a chance to really talk to her much but they just kind of put us on a bed together because I'm a ghost haunting her while she's trying to sleep...

"I was sweating and nervous and I couldn't remember my lines. It took me about two hours to calm down and be able to film the scene with her."

Even worse, she had no idea how to address the Dame.

"I didn't know what to call her," she added. "It didn't feel right calling her Dame Judi or Mrs. Dench. I didn't know how to refer to her."