"Jackass 4" may be Johnny Knoxville's last endeavor with the franchise — one that came with a toll to his physical and mental health.
"I can't afford to have any more concussions," Knoxville, 50, told GQ in an interview published Tuesday. “I can't put my family through that.”
Since 2000 when the MTV slapstick comedy series premiered as a TV show first, Knoxville has experienced four concussions, vertigo, broken bones and lost some teeth among other injuries.
Knoxville and the gang, Bam Margera, Steve-O, Chris Pontius, Dave England and others, have also put their bodies through it for the franchise.
Because of this, Knoxville didn't anticipate filming "Jackass 4." Even Steve-O told GQ that every movie they made was always "declared as the last one."
Still, "Jackass 4" is set to release Oct. 22, but it really could be it for Knoxville.
“You can only take so many chances before something irreversible happens,” Knoxville said. “I feel like I've been extremely lucky to take the chances I've taken and still be walking around.”
Aside from the physical tolls the series has put on the "Bad Grandpa" star over the last 21 years, there were also emotional downfalls. After he entered his relationship with his current wife Naomi, Knoxville started going to therapy because he realized he couldn't live like his old self and still continue the relationship, he told GQ.
There was one topic that was off limits in therapy: why he did the stunts he did. He said he would explore it eventually, but he didn't want to "break the machine."
Knoxville also reflected on his castmates struggles with addiction and the death of Ryan Dunn, who died in a drunk-driving accident in 2011.
“It was heartbreaking, losing Ryan. And it was tough when Steve-O was going off the rails. But he has completely, completely turned his life around and is doing just—I mean, he's doing terrific. He's a different, different man," Knoxville said.
Knoxville said he doesn't blame the reality series for anything, noting each person is "responsible for his own actions," and that as friends they all tried to help each other when one was going through anything.
“We want Bam to be happy and healthy and get the help he needs,” he said. “We tried to push that along. I think that's all I really want to say about it.
Margera will no longer be taking part in this upcoming franchise installment after breaking his contract which required him to attend rehab.
“I don't want to get into public back-and-forth with Bam,” Knoxville said. “I just want him to get better."
