The breakout star of Walk Hard, Jake Kasdan's R-rated spoof of music biopics, could very well be Tyler Nilson -- or, to be more precise, Nilson's genitalia, which shares a good deal of screen time in the film with star John C. Reilly. Nilson's character (named "Bert" according to IMDB) appears at various points throughout Walk Hard, inexplicably -- and hilariously -- naked in every one of his scenes.

In an exclusive interview with ReelzChannel.com, Walk Hard producer Judd Apatow discussed the process involved in casting the role and why Nilson was the right man for the job:

"Jake (Kasdan) had extras casting for someone that was comfortable showing their penis. And then they brought him a big stack of polaroids, and it was all these guys in their underwear, which led to this odd conversation of 'How do we know what it looks like?' Because it could be terrifying. You actually do need the right-looking penis, because the wrong penis could sicken people. If the penis is too large, men might get sad and stop laughing in comparison with this enormous penis. But as we went through the stack, only one guy just was naked. He had the funniest little smile on his face and Jake thought, 'That's the guy.' And that's who he hired."

"For the DVD we actually made a documentary about making that sequence, which we like to call a 'c***umentary,'" he added. The DVD will also include full-length performances of Walk Hard's songs, as well as a two-hour version of the film -- a full thirty minutes longer than the theatrical release -- aptly dubbed "The Self-Indulgent, Almost Unbearably Long Director's Cut."

Check out ReelzChannel.com's Walk Hard page for clips, images and more.

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