John Wick 4's Rina Sawayama Threw Her Back Out The Very First Day Of Training

This post contains spoilers for "John Wick: Chapter 4."

"John Wick: Chapter 4" isn't just full of more action than any movie should be, it's also full of characters — tons of them. Director Chad Stahelski has been expanding the John Wick lore since "John Wick: Chapter 2" when he was tasked with extending a story he'd already told with the first movie back in 2014. Adding new stuff and making the fights more spectacular was his solution, and since then we've been introduced to a bewildering amount of players in the John Wick criminal underworld.

"Chapter 4" introduced Bill Skarsgård's villainous Marquis Vincent de Gramont, Donnie Yen's blind assassin Caine, Shamier Anderson's Tracker, and Scott Adkins' grotesque Killa Harkan, among plenty of others. But while Donnie Yen arguably takes the top spot as the best new addition, there's another fresh face who makes a striking impression early on in the movie.

I'm talking, of course, about Akira Shimanzu, the concierge of the Osaka Continental Hotel and daughter of the late hotel manager Koji Shimazu. Even though the character, played by Japanese-British actor and musician Rina Sawayama, is only in the movie for a relatively brief amount of time, if the end of "John Wick: Chapter 4" is anything to go by, we could be in for a full revenge story centered around Akira in the near future. In other words, it seems Stahelski and co. have big plans for the character. This is great considering Sawayama came close to jeopardizing her involvement in the world of John Wick on her very first day of training.

Rina Sawayama does such a stellar job of playing her bow and arrow-wielding Osaka Continental concierge, it's incredible to think this was her first major film role. Not only does she handle the emotional scenes between Akira and Shimazu like a pro, her combat sequences were as impressive as everyone else's. The musician-turned-actor previously explained how she underwent five weeks of training in Berlin to get her choreography down — which seems like very little considering the intensity of the fight scenes.

But it seems the intensity was, initially, a little too much for Sawayama, who visited "The Tonight Show Starring Jimmy Fallon" and revealed that she threw out her back on the very first day of training:

"In the first week, they were like, 'Oh, we're just going to do some drills just to get you warmed up.' And I think it was honestly the first day of training, I did a move [where] you just dodge underneath. You're in a squat position and you just dodge [...] So, I threw my back out."

Sawayama explained how she didn't tell anyone about her injury, but it turned out she had actually pinched a nerve. And despite her efforts to hide it, the actor's posture was so lopsided after a few days that she eventually had to get treatment.

Thankfully, the injury didn't stop her from completing the job, which is a good thing in light of the way that the "John Wick: Chapter 4" credit scene ended. And despite Akira being Sawayama's first role, she never seemed out of place among the movie's stars, suggesting she's perfectly capable of carrying her own story. That is if Lionsgate should decide to push forward with an Akira project — and Sawayama's back holds up okay.