American History X director Tony Kaye's upcoming film The Trainer officially enters production tomorrow after a winding development path that star and creator Vito Schnabel considered "incredible." Ahead of the first day of production, Deadline reports that Stephen Dorff, John McEnroe, Gina Gershon, and Luke Sabbat are all on board to star alongside Schnabel in his original dark comedy. They'll join fellow co-stars Julia Fox, Stephen Van Zandt, and Taylour Paige in the near-decade in the making production, but there's currently no information on what roles the new additions will play.

The Trainer is based on a script from Schnabel and Jeff Solomon which centers on Jack (Schnabel), a down-on-his-luck personal trainer forced to move back in with his mother in Los Angeles. The film takes place over a chaotic eight-day span in which Jack tries his luck at finding fame and fortune and living his version of the American dream, albeit in a very maniacal, Pain & Gain-like manner. So far, details of the film are being kept under wraps, but we do know Schnabel and Kaye are joined by Jeremy Steckler on the production end with George Paaswell on board as an executive producer.

Dorff's most prominent recent appearance was in Old Henry, a 2021 western from Potsy Ponciroli led by the likes of Tim Blake Nelson and Trace Adkins. He's also known for his roles in the classic films Blade, Zoolander, and I'll Find You, as well as the recent series Detective. The Trainer joins a long line of upcoming productions for the veteran actor which includes the Bruce Willis and John Travolta flick Paradise City.

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McEnroe brings perhaps the most varied career of the four to the cast as a former tennis superstar with a legendary temper turned actor. He's mostly known for appearing as himself in a number of Adam Sandler films, including Jack and Jill and You Don't Mess With the Zohan, though his recent work includes narrating the Netflix series Never Have I Ever. He also has credits for appearances in 30 Rock and had a role in 2018's Ocean's Eight.

Gershon, meanwhile, is a prolific character actress seen throughout massive films like Face/Off and recent series like Riverdale and New Amsterdam. Her most recent appearance was for the Sundance film Emily the Criminal with lead Aubrey Plaza playing a woman wrapped up in a credit card scam that goes way too far. Gershon's also set to appear in the massive video game film Borderlands later this year as the sadistic and sultry Mad Moxxi.

Rounding out the new additions is Sabbat who is best known for starring in Freeform's hit dramedy Grown-ish as Luca Hall. Compared to his colleagues, he's the newest name on the scene with only a few credits in The Dead Don't Die and Lena Dunham's Sharp Stick to his name, but he's already earned recognition with a pair of Teen Choice nominations thanks to his performance as Hall.

The Trainer is still a ways off with an expected release in 2023, but the cast already looks promising as Kaye and Schnabel pull the project from development hell.