Daniel Radcliffe on kissing Paul Dano in Swiss Army Man

In Swiss Army Man (out June 24), Daniel Radcliffe plays a dead guy opposite Paul Dano, the latest in what has become a series of unexpected roles for the former Harry Potter star.

“My very quick pitch is that it’s a buddy comedy/adventure movie in which one of the buddies is dead,” Racliffe told PEOPLE and EW editorial director Jess Cagle in the latest episode of The Jess Cagle Interview. “That would be me. I am the dead buddy. He’s really sweet. I think it’s a movie about accepting our own weirdness and being kinder to each other. Identifying in someone else is an incredibly powerful thing…even if that guy is dead.”

Not sure dead, however, but also flatulent. “There is a scene where [Paul’s character] rides me across the water like a jet ski propelled by said gas,” Radcliffe told Cagle about the film. Did such absurdity make the 26-year-old nervous? “When you read that, there is an element of ‘Okay, yeah, that could be terrible,'” Radcliffe said. “But it could also be maybe the greatest thing I ever get to be a part of. If I’m sitting here in two years watching someone else be a part of that scene, how will I feel? That scene, the first time I saw it, there were tears of laughter and joy in my eyes.”

Because so much of the emotion between Radcliffe and Dano in the film depends on the physical contact, the two actors grew close during production — even going so far as to lock lips. As Radcliffe explained, their kiss was part of a larger connection between the two stars.

“There’s also this very weird, incestuous triangle thing that has happened now with my and Paul’s girlfriends. My girlfriend, Erin [Darke], played Paul’s wife in Love & Mercy, and Paul’s girlfriend, Zoe [Kazan], was with me in What If, and now Paul and I have also kissed on screen.”

“It’s kind of a Bob & Carol & Ted & Alice situation. Or Caligula’s Rome,” joked Cagle.

“That’s what I’m going for in my career — the last days of Rome,” added Radcliffe.

Watch the interview above, and check out more from Radcliffe in the latest issue of EW, on newsstands Friday — subscribe here for more exclusive photos and news, only in EW.