The fake corpse of Daniel Radcliffe will help sell ‘Swiss Army Man’

He was once The Boy Who Lived. Now he’s the Young Man Whose Fake Dummy Corpse Will Ride Around on the Nation’s Buses.

Daniel Radcliffe has been eking out an interesting post-Harry Potter career, and “Swiss Army Man” — which surprised and discombobulated Sundance earlier this year — is his most out-there gambit yet. In the comedy, he plays a farting corpse whose erection can also be used as a compass. Even weirder: the movie will make you think and it might even make you cry.

Radcliffe has been going above and beyond at spreading the word about the film, which opens on July 1. After all, he’s been saying — as he did to us — that it’s the most proud he’s been of a project since his J.K. Rowling days.

But he won’t have to do all the legwork. Over the next month, citydwellers might get the shock of seeing Manny, the actual lifesize dummy the filmmakers used as Radcliffe’s double on set, sitting on buses or in public spaces, wigging out millennials who grew up watching his old franchise. The only downside: The dummy doesn’t fart or get sudden Rodneys.

Alas, you might not get to see Radcliffe himself sitting next to his lifeless doppelganger. That’s what happened to certain New York film journos, who arrived at a secretive mid-day outing only to find themselves on a double decker with Manny, who, everyone agreed, looked pretty good for surviving an entire shoot in the woods and being gnawed on by the occasional raccoon.

Halfway through the trip, Manny was joined by Radcliffe himself, who sat by his doppelganger, posed for selfies and excitedly talked up his new film. (He also stared in disbelief at the bag of movie swag, which included: a beach towel brandished with his dead body, and a collapsible bong.)

“Swiss Army Man” isn’t an easy sell; here we thought “Harry Potter farting corpse movie” were five tantalizing words, and yet most people we’ve said them to have recoiled in horror. But A24 is proving a whiz at shilling difficult product. This year alone they’ve had hits with “The Witch” and “The Lobster.”

The outside-the-box Manny business may be a good way to ease skeptical viewers into a film that’s more than its batty logline suggests — and a way to show them that Radcliffe doesn’t have to just get buck naked (as he did on stage in “Equus” in 2007) to show he’s more than Potter.

Follow Matt Prigge on Twitter @mattprigge