How Zac Efron's 'Greatest Beer Run Ever' bag of brews became a moldy, stinky 'safety blanket'

Chris Evans’ Captain America had a signature shield. Zac Efron’s Chickie Donohue has a duffel bag full of brews.

Based on a true story, director Peter Farrelly’s war dramedy “The Greatest Beer Run Ever” (now streaming on Apple TV+) lives up to its title, with Chickie’s improbable and rather crazy mission traveling from New York to deliver cans of beer to his friends serving in Vietnam. He needs something to carry all that booze and his signature defining accessory – other than a sweet 1960s mustache – is a green bag emblazoned with “Doc Fiddler’s” (the name of Chickie’s local bar).

During filming, “that bag did become a safety blanket for me. It was weird,” Efron tells USA TODAY. “The sun's still coming up, we'd be rehearsing and if the bag wasn't around, I wouldn't know where I was supposed to be or where Chickie would be. I had to take into account that I've got this bag. Sometimes, it would prevent me from sitting down or really from turning fully. I didn't feel right without it.”

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Sometimes, the bag served a practical purpose: In one scene, Chickie has the bag on his head during a storm to block the rain.

“They've become like a team,” Farrelly says. “It's his buddy keeping him dry.”

Adds Efron: “Dry and inebriated.”

The number of beer cans dwindles as Chickie finds his four friends and gives them beer, while trying not to die or get arrested. But because the movie filmed scenes out of chronological order, Farrelly regularly had to do math to figure how many beers needed to be in the bag at any given time.

“Luckily, that’s not my job,” Efron quips.

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They start with 48 beers in the bag, and when Chickie first gets to Vietnam, he parties all night with a group of MPs, including his pal Tom Collins (Archie Renaux). Farrelly figures they went through three cases. Chickie had one left afterward, and from there, “we kept track along the way,” the director says. He had some in the foxhole with buddy Rick Duggan (Jake Picking) and fellow soldiers, and later with other friends Kevin McLoone (Will Ropp) and Bobby Pappas (Kyle Allen), “and he had some just walking along.”

“Yeah, because he had nothing to drink,” Efron says. “He didn't have bottled water.”

The bag was important for Efron, but just like a cold one left untouched for a while, it got a little rank. 

“After the first two weeks, that thing stunk, man,” Efron admits. “It was in the mud, the rain, it was carrying sweaty clothes and popped-open beers. At some point, it started to mold on the inside. So this thing just gave off an odor. I would set the bag down and (go) over to some of the other actors and they'd go, ‘Jesus, what's that smell?’ I'm like, ’It’s me.’

“I realized the bag had permeated my wardrobe fully, and it just stunk like moldy stale beer and sweat.”