EXCLUSIVE: Channing Tatum Opens Up About Learning to Tap Dance for 'Hail, Caesar!'

The 36-year-old star says he had no idea 'how hard it was going to be' in this behind-the-scenes DVD featurette.

In Hail, Caesar!, the Coen brothers' recent tribute to classic Hollywood, Channing Tatum steals the spotlight as Burt Gurney -- an old-school song and dance man.

While Tatum's role might have only included a few scenes in the sprawling period comedy, his introduction in the film comes in the form of an intricate and stunning musical dance number that harkens back to the era of Gene Kelly and Fred Astaire.

ETonline has an exclusive behind-the-scenes look at how the breathtaking number all came together, and according to Tatum it was more difficult than he ever could have imagined.

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"I, in no way, shape or form, knew how hard it was going to be," the actor admitted in the DVD featurette. "I just figured that I could learn the tap movement, and it would make the sound. But what I found is that you really need to be musical."

The musical number, "No Dames," features Tatum’s character as a sailor who is about to ship off to the war and -- along with over a dozen of his fellow dancing Navy men -- is lamenting that he "ain’t gonna see a dame" while on the high seas.

The number called for Tatum – who got his start in show business in music videos before breaking through in 2006 dance drama Step Up -- to dance on the bar top, jump from table to table and hang off of banners on the ceiling, all while perfectly nailing the tap aspect of his performance.

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"I don't even think they should call it 'tap dancing.' They should just call it 'foot percussion' or something," the 36-year-old actor said with a laugh. "You are dancing, but really you're playing a part of the song."

Chris Gattelli, who choreographed the "No Dames" number, gushed over the Magic Mike star's innate ability to perform and his willingness to learn an entirely new style of dance.

"He's so talented, and he's picking it up so fast and working incredibly hard," said Gatelli, who added that Tatum managed to hold his own against some of the best tap dancers in entertainment.

Hail, Caesar! comes out on Blu-ray and DVD June 7.