EXCLUSIVE: George Gallo’s movie Bigger about Joe and Ben Weider, the founders of the Mr. Olympia bodybuilding contest, has tapped Mr. Universe 2014 Calum Von Moger to play Arnold Schwarzenegger onscreen. The brothers, who co-founded the International Federation of Bodybuidling, discovered Schwarzenegger and encouraged him to come to the U.S. Prior to being a blockbuster action star and Governor of California, Schwarzenegger was a seven-time Mr. Olympia-title holder. Back in 1972, the Weider brothers sold a nutritional supplement, Weider Formula No. 7, that featured a young Arnold Schwarzenegger on the label.

Also joining the cast of Bigger, which is currently shooting in Alabama, are Robert Forster, Tom Arnold, Max Martini, DJ Qualls, and Steve Guttenberg. Previously announced, Tyler Hoechlin plays Joe Weider, Dunkirk‘s Aneurin Barnard plays brother Ben, Kevin Durand is the brothers’ nemesis, fitness magazine publisher Bill Hauk, Julianne Hough plays Joe’s first lady of fitness wife Betty, Victoria Justice is Joe’s first wife while Colton Haynes will play Jack LaLanne.

With the latest round of casting, Guttenberg plays Louis Weider, Joe’s father. Forster plays the older version of Joe Weider. Tom Arnold portrays Roy Hawkins, the publisher who gave Joe Weider distribution on his first real magazine. Martini is Jerry George, the sidekick to Bill Hauk. Qualls will play Mike Steere, the journalist who co-wrote the Weider brothers’ book Brothers of Iron: Building the Weider Empire.

Steve Lee Jones, Bee Holder Productions, is producing with Scott LaStaiti. Executive producing are Eric Weider and Camila Castro, Bee Holder Productions. Bigger was written by Brad and Ellen Furman, Andy Weiss and Gallo.

Von Moger is repped by Vladar.