In Hulu’s “Reboot,” a meta comedy from “Modern Family” creator Steven Levitan, Johnny Knoxville plays edgy stand-up comedian Clay Barber. After multiple stints in jail, he gets the chance to reprise his role in a wholesome family sitcom after, yes, Hulu, decides to reboot it 20 years later.

Unlike Clay, Knoxville is “very good” at dubbing lines and is — at least according to his co-star Keegan-Michael Key — “an absolute gentleman.” But the 51-year-old actor and stuntman admits that there’s “more than a little” of himself in his character. Both were branded as bad boys and lived fast lifestyles in the public eye. Eventually, Knoxville had to cool off, and in the cleverly named “Reboot,” Clay works to turn his life around and stay sober.

Speaking about his own journey, Knoxville tells Variety, “I had to slow down. I was running hot. You’re a fool if you live like...