Michael J. Fox makes surprise appearance with Coldplay

It was a blast from the past when actor Michael J. Fox made a surprise appearance at the Glastonbury Festival, playing guitar during Coldplay's "Fix You."

Video shared by CBS News partner BBC showed Chris Martin directing the spotlight to the retired "Back to the Future" actor as he appeared on stage. Fox, in a wheelchair, played a guitar in his lap.

Martin then told the crowd Fox had been key in Coldplay coming together.

"The main reason we're in a band is because of watching 'Back to the Future,'" he said. "Thank you to our hero forever and one of the most amazing people on Earth, Mr. Michael J. Fox. Thank you so much Michael, our hero."

This isn't the actor's first appearance alongside the band. Fox previously made an appearance with the rock band in 2016, playing "Johnny B. Goode."

In 2022, Martin told Kelly Clarkson that watching Fox play the Chuck Berry song from the 1985 movie inspired him to become a musician.

"That's what made me want to be in a band, you know? That scene," he said.

Fox also posted a tribute to the band saying, "This is @coldplay's time."

"Glastonbury all the love and thanks to the @coldplay team who took such great care of us. And many thanks to Chris, Will, Johnny, Guy and Phil," he wrote on Instagram . "Oh yeah in case you were wondering…it was f*cking mind blowing."

Fox was diagnosed with Parkinson's disease in 1991 at age 29. The star has been vocal about his battle, recently telling Variety about the injuries he has gotten from losing his balance.

The neurological disorder causes unintended stiffness, shakiness and difficulty with coordination, and worsens over time, according to the National Institutes of Health .

Fox also spoke about his experiences in a recent interview with CBS "Sunday Morning," in which he reflected on how long Parkinson's has been part of his life.

"It's been 30-plus years; not many of us that have had this disease for 30 years," he said. "It sucks having Parkinson's."

Since going public about his illness in 1998, Fox has worked to raise money for Parkinson's, a disease he learned was underfunded for research and treatment development. The nonprofit Michael J. Fox Foundation, which was founded in 2000, has raised more than $1.5 billion for Parkinson's research, according to its website .