A new character emerges in the Adam McKay-Will Ferrell beef: Michael Shannon

Michael Shannon has entered the chat.

Fresh off his latest Oscars nomination, Adam McKay is still doing damage control over his split from collaborator, muse, and star of his funny movies, Will Ferrell. Thus far, the story has been that Ferrell wanted the role of late Los Angeles Lakers owner Jerry Buss in McKay’s upcoming HBO series Winning Time, which tracks the rise of the Lakers basketball dynasty. Instead, however, McKay gave the role to their mutual friend and artistic partner, John C. Reilly. But that’s not the whole story.

Per The Hollywood Reporter’s fascinating behind the scenes look at the series, Michael Shannon, the furrow-browed, square-jawed dramatic actor known for roles in Knives Out and Boardwalk Empire, was initially cast as Buss. Shannon and McKay go way back, getting their start on improv stages in Chicago. But, as McKay puts it, “Will was good with it.”

Things turned when production got underway, and McKay’s style, which requires a lot of turning directly to the camera and explaining the intricacies of a situation (yup, he’s doing that again, too) didn’t mesh with Shannon’s process. “It really bugged Michael that we were breaking the fourth wall,” says McKay, referring to the direct-to-camera format for which the filmmaker is now well-known. “He kept saying, ‘I don’t like this. It throws me. I’m having a hard time.’”

Because this is now a fixture of McKay’s style, Shannon left, and the director needed to find a new lead for the show, so instead of returning to Ferrell, who, again, really wanted the role, he hit up the actor’s best friend, John C. Reilly. “I told [Reilly], ‘We’re in a weird spot here, but I’m directing the pilot and I think you’d destroy this,” McKay remembers.

Meanwhile, Reilly was licking his wounds from Holmes & Watson, a box office fiasco he starred in with Ferrell and the rare recipient of an A.V. Club “F” letter grade. “I’d been sitting at my kitchen table, thinking, ‘Man, I’m dead in the water, all this work, 80 movies, and I got nothing going on,’ when I got the text from Adam,” he recalls.

At the time, McKay says that his friendship with Ferrell was in a “weird moment where Will and I weren’t exactly hugging each other.” But Reilly did what he thought necessary and reached out. “Will was very hurt that I wasn’t the one to call him,” McKay says. “I should have. I fucked up.”

For his part, Reilly was diplomatic regarding the situation. “Will is one of my best friends, Adam is one of my best friends,” he said. “I was delighted to get the job and that’s all I really have to say.”

Winning Time, which is already prepping its second season, premieres on HBO on March 6.