Seth Rogen told a TV audience that he’d been bemused when he first encountered Grateful Dead fans in Las Vegas – but later that night became one of them.

During a recent appearance on Jimmy Kimmel Live! Rogen reminisced with guest host Kathryn Hahn about the time they were in Sin City, working on upcoming comedy series The Studio. The two-week visit coincided with one of Dead & Company’s residency shows at the Las Vegas Sphere.

“It was like normal Las Vegas for the first week and a half – and then one day our casino was just filled with bald men with ponytails and tie-dye shirts,” Rogen said, expressing his bewilderment. “We were like, ‘Oh, the Grateful Dead is here!’”

READ MORE: Dead & Company Kick Off Sphere Residency

He told Hahn cautiously: “I can’t speak for everyone, but I did a ton of acid, and then went to the Grateful Dead show with everybody, and with you. It blew my goddamn mind! It was really something.”

Hahn admitted: “I didn’t know any of the music and I danced the entire time.”

Rogen agreed with her sentiment: “It was weird to hear a band for the first time – and then for them to become your favorite band of all time! ‘I don’t know this song but it’s the best song I’ve heard in my entire life!’”

Why Dead & Company Changed Their Minds About Quitting

Dead & Company’s Sphere residency began in May and runs until Aug. 10. The band had previously decided to retire, but the possibilities offered by the $2 billion venue were too enticing to refuse.

“I think what we all love is that there’s finally once again a live-music space race,” guitarist John Mayer told the L.A. Times in a recent interview. “There’s the social-media space race, the podcast space race, the AI space race. But live music pretty much stayed the same for such a long time.”

He attempted to deny any ego was involved before allowing: “Well, it’s a little ego.” But he added that was overridden by the desire “to delight and surprise people more than they expected to be with this big, empty canvas and this really big palette.”

Watch Seth Rogen Recall His Grateful Dead Experience

Dead & Company Sphere Opening Night Photos

The group kicks off their 'Dead Forever' residency with a dazzling visual show.

Gallery Credit: Matthew Wilkening

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