Earlier this week, Chris Martin stopped by a London homeless shelter and brought his guitar along. Among the songs he played was Wham!’s holiday classic, “Last Christmas,” which he sang with one of the shelter’s guests. The song’s composer and original singer, George Michael, passed away this week.

“A huge thank you to Coldplay's Chris Martin for dropping by our Crisis at Christmas centres and entertaining our guests!” Crisis wrote on its Facebook page with the below video. “Here he is performing a wonderful tribute to George Michael with our very own King of Karaoke - #CrisisXmas guest Kevin!”

The clip was found by Rolling Stone, who also discovered an Instagram post by a volunteer at Crisis named Matthew, who wrote that Martin showed up “with no fuss, no fanfare and no press, to help make tea and coffee and also play guitar so guests can have a sing song."

According to its website, Crisis is “the national charity for homeless people. We are dedicated to ending homelessness by delivering life-changing services and campaigning for change.” Their aims are to “to do more for more homeless people in more places across the U.K. and help to change their lives for good” and to “change the way society thinks and acts towards homeless people.”

George Michael was found dead on Christmas Day by his partner, Fadi Fawaz, in his home in Goring-on-Thames, Oxfordshire. The cause of death has not yet been determined. Michael, who rose to multi-platinum stardom as a member of Wham! before going on to a even more successful solo career in 1987, was 53.

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