"We're rehearsing this scene where we're supposed to take our clubs over our head … I pretend to throw my club and I hear, 'oh my God', I turn around and the f***ing camera man is knocked out. Come find out, Joe (nailed) the camera man," Johnson says in the video.
Johnson captioned the video as "one of the funniest f***ing things I've ever seen" and it's hard to argue.
Reigns clearly felt horrible about the insane mishap and apologised profusely to the cameraman who copped the full force of the wooden club and can be heard in the background telling him to take a freebie punch at his face.
Thankfully the cameraman was able to get back behind the camera and capture the rest of the fight scene without needing to deliver the punch.
Reigns made an emotional return to the WWE in late February after revealing his leukaemia battle in October.
The 33-year-old left the wrestling world stunned when he confirmed he would be taking a break from the company to fight a new battle with leukaemia.
He revealed at the time he has battled leukaemia for 11 years, since he was first diagnosed as a 22-year-old.
But he proudly announced he was in remission and now is back in the ring and is making a splash during his big screen debut.
Hopefully his next scene he listens to the directors instructions and doesn't take out any more cameramen.
