'Deadpool' Costars Ryan Reynolds and TJ Miller on Improvising

“Deadpool” was always going to be a movie that featured plenty of improv.

“We’re all messing around,” confesses Ryan Reynolds during an interview with Made in Hollywood.  “There has to be,” he says, “it’s a ‘Deadpool’ movie”

His costar TJ Miller admits that Reynolds is “such a good improviser” and most of the humor comes from their interactions to “riff” on each other throughout filming. “When he improvises as Deadpool,” Miller adds, “it’s almost like they’re writing dialogue for Deadpool.”

The anti-hero’s full-length feature debut tells the story of his origins as ailing Special Forces operative Wade Wilson, who undergoes a life-saving medical experiment that leaves him with incredible new abilities and a new lease on life with accelerated healing powers.

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But his new supernatural gifts have drawbacks–like a disfigured face that Miller, as his friend Weasel, compares to “the topographical map of Utah” in the trailer.

Taking on the new secret identity as Deadpool — clad in a red suit and mask — he goes on a mission seeking revenge against his enemy.