Watch Keanu Reeves act out his most dangerous scene in 'John Wick: Chapter 3'

Every new chapter in the John Wick franchise means a fresh opportunity for star Keanu Reeves — who plays the titular dog-loving assassin — to put his life in danger for our entertainment. For John Wick: Chapter 3 — Parabellum, out in theaters on Friday, the actor pulled off one of his craziest stunts yet: fighting a squad of motorcycle-riding killers while navigating the Brooklyn streets on horseback. It’s an insane idea that Reeves and director Chad Stahelski had been wanting to try for years.

“John Wick in a suit on a horse? C’mon,” the stuntman-turned-filmmaker tells Yahoo Entertainment. “Early on in development, I made a list of everything [Keanu] was good at. He was like, ‘I think John Wick should be on a horse,’ and I [said], ‘That’s a great idea.’” (Watch our video interview above.)

For Stahelski, putting his deadly hero on horseback connected Parabellum to the Sergio Leone spaghetti westerns like that he grew up loving. But for Reeves — who learned to ride for his 2013 film 47 Ronin — it meant a lot of pre-production training, as well as a unique wire system. “I worked with a wonderful riding master and stunt supervisors, and they created this contraption to help me be safe and go over the side of a horse on a wire,” the actor explains. “I don’t think that had ever been done before.”

The wire system came in handy whenever the horse bolted, causing Reeves to slip off its back. “There was a gentleman on a wire who could pull me up off the ground,” he says, adding that there were still a few “sketchy moments” despite all the safety precautions. “When I went over the side of the horse, the horse took off and then you’ve gotta get your feet of the stirrups. And then you just make yourself small so you don’t hit anything.”

Consider that a new life lesson: “Get small, but also get your feet out of the stirrups.”

John Wick: Chapter 3 — Parabellum rides into theaters on May 17. Watch the trailer:

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