'An American Pickle' trailer: Seth Rogen stars as bearded time traveler and his great-grandson in comedy

With some comedies, the laughs start with the title and absurd premise.

Take "An American Pickle," which features Seth Rogen in dual leading roles as 1920s immigrant Herschel Greenbaum, who is brined alive for 100 years after falling into a factory vat of pickles and re-emerges in 2020 to live with his Brooklynite app developer great-grandson Ben.

"There was a real sense from people I know that thought maybe it was a joke and not an actual movie that we were spending huge amounts of time and energy working on," says Rogen, whose "Pickle" will silence skeptics. The film is bypassing a theatrical release to stream on HBO Max (Aug. 6, with a trailer that dropped Friday). "It was in fact real. So I'm excited to show it to people."

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Based on a New Yorker novella by Simon Rich, who adapted the screenplay, "American Pickle" marinates in the premise of what it would be like for a man in 2020 to meet his same-age great-grandfather.

"What would he think of me?" asks director Brandon Trost, a longtime Rogen collaborator. "The ultimate answer is that he would probably hate me or basically think I'm living the wrong way of life. Old world ideals are so different from what they are now."

Shooting both lead roles with Rogen required technical acumen and split-screen technology made painstakingly difficult by Rogen's insistence on spending months growing his own beard. "I've done many movies through the years. The one thing that is consistent is that fake beards look terrible," says Rogen. "We didn't use any fake beards throughout the entire movie."

This meant a hirsute Rogen shot his scenes as Herschel before shaving the colossal beard ("it felt great, because that beard was getting to be a nightmare"). The crew returned to each location a month later, placed the camera in the exact same position and had Rogen complete the dialogue using an earpiece for exact timing.

Then the conversational moments were synced together with eye contact and movements perfected, even during a living room dance between the two.

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"Those kinds of things from a technical standpoint are actually wildly complicated to achieve, but the illusion is making them feel loose and off-the-cuff," says Rogen of dancing with himself. "Sometimes you want people to notice the effort. But in an ideal world, no one will even think about how difficult that was."

Things get difficult onscreen for modern-day Herschel, whose outdated modes of thought make him a Brooklyn pariah, then nationally loathed in a socially satirical turn. "He's from an era of different sensibilities and refuses to update to the times as he should," says Rogen. "Unfortunately, that is something that is highly praised in our culture."

But the "unique" story does allow Rogen to show off some physicality as Herschel proclaims he will "make violence" with his fists in brawls, and impressively sprints away from angry crowds. Rogen shows he can sprint and insists it's no camera trick.

"I'm actually not incredibly incapable physically, but every character I've ever played is a disaster," says Rogen. "Herschel might be the first time I played someone who runs normally and beats the (expletive) out of people."

Yet he never goes gherkin. Despite the title, Herschel's fateful vat fall and his later development of a trendy Brooklyn pickle brand, Rogen never indulged in the old-fashioned treat.

"What's funny is, I didn't eat one pickle throughout the entire movie," says Rogen. "Herschel doesn't get high on his own supply. Those pickles are for selling."

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This article originally appeared on USA TODAY: 'An American Pickle' trailer: Seth Rogen talks 'unique' HBO Max comedy