T.J. Miller keeps pace in out-there 'Deadpool'

T.J. Miller is pretty sure he knows how the casting conversation went for Weasel in Deadpool.

In Miller's scrambled brain, the filmmakers pondered who wouldn't overshadow Ryan Reynolds (as the main character Deadpool) and his classic leading-man looks.

"They all asked if there was anyone out there who looks like his superhero power is spilling mustard on his shirt. Or who was bitten by a radioactive spider as a child," says Miller, 34, says during a highly random phone conversation. "And each of them, each at once, said 'T.J. Miller.' End of conversation."

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That story is no doubt as false as the idea that Reynolds was remotely good-looking through much of Deadpool (he's mostly masked or suffering severe skin mutilation).

But it shows what Deadpool's filmmakers were truly looking for in Weasel, the wisecracking, opportunistic best friend in the movie that smashed February records at the box office ($132.8 million in three days).

Miller had to have the random chops to be as out-there as the fast-talking Deadpool. In their scenes together, Miller matches Reynolds shot for bizarre shot.

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"We have a main character who is so outrageous and irreverent, we needed someone who could keep up with Ryan," says producer Simon Kinberg. "We knew that T.J. would bring that."

The stand-up comic has a powerful résumé of craziness, whether as say-anything entrepreneur Erlich Bachman in HBO's Silicon Valley or the real T.J. Miller, who smashed an egg on his face last month on The Late Show With Stephen Colbert.

Miller also has previous experience as a tentpole franchise sidekick, playing Lucas Flannery, who drove around land-locked farmland with a surfboard on his car during Michael Bay's Transformers: Age of Extinction.

Sadly, that stint was brief, as Flannery was charred to a crisp by Decepticons mid-movie. So while Transformers 5 will come to screens in 2017, Flannery will not likely be present.

"Who knows, Michael Bay might turn me into a Transformer for the next one," says Miller. "TBD."

Miller also gives strangeness his total all, which included some "Christian Bale training" for Weasel, which he insists consisted of spending times with weasels in the wild.

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"I learned their language and gave them names, I even married a weasel," Miller says.

If somehow that were true, it was for nothing. When Miller tried to act for real and incorporate a thespian-like facial tic for Weasel on his first Deadpool take, director Tim Miller stopped him.

"Tim was like, ‘Hey, are you doing some sort of facial tic?' And I was like, 'Yeah,' " Miller recalls. "He told me to stop. It was like, everything else you're doing is great. But don't act. Do your comedy."

The comedy will not always be pretty. Miller says the uber-confident Erlich will suffer a truly difficult third season in Silicon Valley, which returns April 24.

"You really start to feel sorry for him," says Miller. "I'm truly trying to educate the public that I do some (crazy stuff). Sometimes comedy is down and out."

But at least his Weasel wasn't destroyed in Deadpool, leaving the character open to return in the planned sequel.

"The only thing better than being in Deadpool is the prospect of doing Deadpool 2," says Miller.