If there were a candidate for the funniest actor in The Five-Year Engagement, comedian Kevin Hart would justifiably be at the top of the list. Leading funny man Jason Segel would be up there, too. But, according to Hart, the distinction of funniest star belongs to someone else. "I’m going to have to go with Emily Blunt," Hart said in our exclusive interview. "[She] is beyond hilarious, man."

What makes Blunt so funny, aside from her ability to deliver icy one-liners, as she famously did The Devil Wears Prada? "First and foremost, her personality is amazing," Hart explained. "She is so laidback, and that’s one of her great qualities. It kind of shines on set. So, you know, in a work environment, she’s fun, she’s not afraid to laugh and have a good time outside of takes, and I think that’s what makes her that much of a better actress."

On set, Hart added, Blunt's sense of humor sometimes got the best of her — an infection that spread to the entire cast. "We had a day where we were improvising and [Blunt], literally, could not keep it together," Hart recounted. "Just this one thing had her laugh – for a least – it might have been two hours of giggles. Her laughing was like a trickle effect. Everybody else started to laugh. We – literally for like two hours — we couldn’t get through a take."

Watch the trailer for The Five-Year Engagement here: