Funnyman Jim Carrey is following up his 'Yes Man' hit with 'I Love You Phillip Morris,' a dark comedy co-starring Ewan McGregor -- and ET's with the pair at a special Sundance dinner! Watch the video to see who comes over and plants a kiss on Jim's lips in the middle of his interview (Hint: It's not his longtime love, Jenny McCarthy)!

"This is one of the special ones," Jim tells ET about the project. "There are very few scripts that you get in your hands that you would pay to do, and this was one of those ones. It's just a very original idea and based in reality; a real story of a real guy that was just was relentless about love -- and he went about it the completely wrong way."

Based on true events, Jim plays Steven Russell, a married Texas father and former cop who became a con man -- and fell madly in love with his cellmate, prompting him to repeatedly escape from prison to be with him.

"He's one of those guys who just could've gone legit and done quite well, but, like me, decided to choose white collar crime," jokes Jim, who adds that he had to get into the proper mindset for his romantic scenes with Ewan.

"You just had to put out of your head the idea of your sexual proclivity," he explains. "You just love a person and find all of the things about that person that you love in yourself; that's how it works, male or female or whoever it is, love is love -- respect for people, respect for the project."

At this stage in the interview, Ewan interrupts to say hello and plant a friendly kiss on Jim's lips.

"Jim's a very firm but tender lover," jokes Ewan, "and a little prickly, but that adds to it in a way, don't you think?"

Watch ET for more with Jim and Ewan!