“Yellowstone”'s Luke Grimes recalls man having a heart attack during his festival set: 'Everything's okay'

The actor also revealed the ill-titled song he nearly played after the emergency that was thankfully caught and nixed by his manager.

Luke Grimes is reminding everyone of the importance of playing certain situations by ear. 

While visiting The Tonight Show on Tuesday, the Yellowstone actor and singer recalled a scary moment in which he was performing at an undisclosed music festival and someone in the audience suffered a medical emergency. Host Jimmy Fallon prefaced the story by revealing that the man involved in the incident, to both of their knowledge, is doing just fine now. 

“You’re always thinking before you got on stage, like, what could happen wrong on the stage?” Grimes said. “We’re playing this big festival, huge crowd. I’m looking around, making sure everybody’s vibin’, having a good time, and I see this one section of the audience that they’re all worried and they’re pointing at the ground and something’s clearly wrong.”

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Related: Everything to know about the Yellowstone cast and their lives off the ranch

The “No Horse to Ride” singer immediately paused the show and called for assistance. “It turns out a guy had a heart attack,” he revealed, before quickly adding, “Again, from what I know, everything’s okay, so I’m not being an [bleep] telling the story.” 

Grimes explained that he and his bandmates stood offstage for roughly 30 minutes while emergency services emptied out a large portion of the crowd and brought forth an ambulance to help the man. After the situation was safely handled, Grimes was informed that they’d have time for “one more song” if they’d like to return to the stage. 

“I’m like, ‘Well, I don’t really feel like playing music anymore, but, okay,’” he said. “So I’m like, ‘Let’s just do the closer, boys.’ We always close with the same song."

Fallon commended Grimes for heading back out and finishing his set. “Yeah, I know, I felt bad. I wanted to give them their money’s worth. So we go out and we’re about to start playing the closing song and I see my manager out the corner of my eye being like, ‘NO!’” He said, making a show of waving his arms in the air.

Then, he confessed, “The song that we always play at the end is called ‘Ain’t Dead Yet.’ And none of us thought about it!”

Related: Where we left off in Yellowstone season 5

The audience let out an audible groan at Grimes’ revelation, while Fallon collapsed onto his desk in laughter. “Again, everything’s fine!” Fallon insisted as the show's house band, the Roots, played a whomp sound. “Everything, as we know, is fine!”

Fallon then praised Grimes’ manager for preventing him from inadvertently ending his music career. “Thank God he caught it. So stupid!” He said, noting that they "pivoted" to another song instead.

Watch Grimes recall the incident — and try his best to avoid spilling Yellowstone secrets — in the clip above.