Fassbender outs Marion Cotillard's flatulence

Mega stars Michael Fassbender and Marion Cotillard were in Australia to promote their latest flick Assassin's Creed, but the Fass took a crass turn when the small-talk turned crude.

Our Be reporter Liz asked the pair to spill on the shameful secrets they learnt about one another on-set and Michael joked about Marion's issue with flatulence. Yep...

"Your flatulence" said Michael to Marion. "But we're not going to talk about that. That wouldn't be right."

Marion responded between giggles: "Please, let me be a glamorous actress. I should have never..." before trailing off.

She then added: "I thought about it yesterday and was like, 'Did you really tell the story about farting?"

Michael jumped in to graciously save the actress with a lifeline: "We all fart, let's face it."

An embarrassed Marion responded: "Yeah, but we keep it for ourself," before changing the subject by joking her English wasn't up to scratch.

The duo star in the video game-turned-movie Assassin's Creed, which sees Callum Lynch/Aguilar (both played by Michael) jump into the memory of his ancestor to learn the skills of a Master Assassin to protect an ancient artifact.

Marion plays Dr. Sophia Rikkin, who seeks to unlock Lynch/Aguilar's memories to discover where the ancient artefact lies.

Both actors admit the sci-fi film is a far cry to anything they've filmed before.

And if you're expecting saucy love scenes between the two, think again.

Hollywood's hottest stars laugh at the idea they're even sex symbols.

"I don't feel like I've played a lot of beautiful and sexy or glamorous women but I never compare things that I've done in the past with things I'm doing," explained Marion.

"I only look for different things to do and just exploring the unknown is something I love to do... and this universe of Assassins's Creed was something I'd never explored before."

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As for Michael? "I never set out to play a sex symbol... that sort of seems absurd."

Assassin's Creed is in cinemas from January 1.

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