Joss Whedon Had A Warning For The Russo Brothers Before They Entered The MCU

Spearheading the biggest superhero franchise in the world is a strenuous job — Joss Whedon would know. The "Buffy the Vampire Slayer" creator wrote and directed "The Avengers" and its sequel "Avengers: Age of Ultron," both ensemble superhero films teeming with a multitude of characters and interweaving storylines. Whedon faced his fair share of struggles while writing for the Marvel Cinematic Universe: the filmmaker described balancing characters to be nothing short of a "nightmare."

Whedon, who also created the MCU-set TV series "Agents of S.H.I.E.L.D.," hasn't directed a feature film since "Age of Ultron," though he did complete reshoots on another superhero project, "Justice League." His retreat from the public eye has largely been the result of allegations of abusive behavior that date back to "Buffy the Vampire Slayer," but based on his advice to his successors at Marvel Studios, the pressures of handling the "Avengers" movies may not be an experience that Whedon wants to repeat.

When "Captain America: Civil War" directors Anthony and Joe Russo were tapped to helm "Avengers: Infinity War" and "Avengers: Endgame," Whedon had only one piece of advice to share: start training.

'I'm deadly serious'

The Russo brothers had to direct a bunch of superheroes engaging in battle on the silver screen — but it's not just the actors who need to watch their diet and commit to the gym. In an interview with Den of Geek, Whedon said the Russos didn't have much to worry about; they already had a "versatile" background thanks to their experience with "Arrested Development." However, he also pointed out the "physical toll" of making MCU movies, which he described as "phenomenal."

"I think they came from 'Arrested Development,' they are very versatile, that's the thing you need to be. Honestly, my only advice to them is 'start training. Get a trainer, and start eating protein.' [Everyone laughs] I'm deadly serious. The physical toll of making these things is phenomenal. And it's going to be twice the price."

The filmmaker elaborated that he'd had a challenging time directing the films since he was "going home and rewriting" the script every night. Fortunately, it helped that the Russos were a team of two and had each other's support.

"I don't know about them, but they won't be going home and rewriting it every night like I was. And there's two of them. But I don't sleep! So, I'm very careful of staying away from the doughnuts. I don't need to be hyper for 20 minutes and then be sleepy, I can't afford that, ever."

Since Joe and Anthony Russo took over, the filmmaking duo have successfully shaped the MCU as we know it. They've directed "Avengers: Endgame," the highest-grossing superhero movie of all time, and managed to execute a cohesive conclusion to the Infinity Saga. They're now taking a break from the MCU to focus on other projects – Joe Russo said last year that "we won't be ready to do anything with Marvel until the end of the decade" — but at least that means they can eat the occasional doughnut.