Colin Farrell and Brendan Gleeson reveal the ingredients of fake movie Guinness: 'All sorts of unspeakables'

Colin Farrell and Brendan Gleeson are pulling back the curtain on one very serious ale-ment that they've struggled with throughout their careers.

The actors, who star in The Banshees of Inisherin, revealed that, before a non-alcoholic version of Guinness was created, they used to have to drink fake movie beer that was made up of "all sorts of unspeakables" in order to recreate the look of the iconic beverage onscreen.

"Everything was ghastly," Gleeson shared on a recent episode of Late Night with Seth Meyers. "It was actual cream…"

Farrell then interjected, "Grape juice with cream! All sorts of drinks you shouldn't be mixing." If that didn't sound appetizing enough, the actor noted that the cream itself was often "curdled" too.

"Flat Coke and stuff like that with all sorts of unspeakables on top of it," Gleeson added. "It was okay, but if you had a lot of takes, and you had to drink in it, it was just… I mean, Il faut souffrir, they say. It's important to suffer… for art. And this was suffering."

Thankfully, when it came to shooting their new film, the close friends were able to drink Guinness Zero on set instead of the old grotesque alternatives they'd had in the past.

"Thank God for it," Farrell swore. "On the production, we would've had to drink just an unutterable amount of [bleep]. And it's not [bleep]. It's actually really tasty."

Jeff Spicer/Getty Images Brendan Gleeson and Colin Farrell reveal the ingredients of fake movie Guinness: 'All sorts of unspeakables'

While Farrell noted that Gleeson didn't love a glass of the alcohol-free pint ("he likes the proper stuff"), he has quickly hopped onto the alcohol-free train. "It's delicious," he said. "I've given it to a few other people who are, you know, stout aficionados who are like, 'Jesus, that's an eight.'"

Watch Gleeson and Farrell share movie industry drink secrets above.

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