NEW YORK (AFP) - R.E.M. frontman Michael Stipe has stayed mostly out of public view since the alternative rock pioneers broke up four years ago.
But on Monday, as the audience was just settling in, Stipe walked unannounced onto the stage sporting a stocking cap, suit-and-tie and gray stubble.
The occasion was the 68th birthday of the rock icon Patti Smith, who not only roused Stipe from semi-retirement but has planned an active year ahead, including a sequel to her acclaimed memoir.
Stipe, hardly ever an "opening act" since R.E.M. took off on college radio stations in the 1980s, sang a six-song set before 1,500 people at New York's Webster Hall as Smith's daughter, Jesse Paris Smith, accompanied him on keyboards.
The R.E.M. singer, with a touch of irony, sang the theme from New York, New York - most famously performed by Frank Sinatra - but otherwise showed himself to be in a meditative mood.
He offered a tribute to the "beautiful and eternal" Vic Chestnutt, the folk singer who died from a suicidal drug overdose on Christmas Day 2009.
Stipe acknowledged his lyrical debt to Smith - whose Gloria delivered one of rock's most famous opening lines, "Jesus died for somebody's sins but not mine" - as he closed with the dreamy R.E.M. song New Test Leper, which begins, "I can't say that I love Jesus / That would be a hollow claim."
The Georgia-bred singer, 54, has not performed since 2008 with the exception of singing the R.E.M. classic Losing My Religion at the urging of Coldplay's Chris Martin at a charity concert at New York's Madison Square Garden after Hurricane Sandy.
After a fan shouted, "I miss you," Stipe retorted, "I missed me, too."
ENERGETIC 'GODMOTHER OF PUNK'
While Stipe has turned reclusive, Smith has embraced her title of "Godmother of Punk."
Along with a second concert Tuesday at Webster Hall, she plans a series of similarly intimate shows on the US West Coast.
Smith has kept an active if eclectic touring schedule, playing in recent years with fellow musical giants including Morrissey and Neil Young, even as she pursues more fully her passion for writing.
Just Kids, her 2010 memoir that explored her relationship with photographer Robert Mapplethorpe as they wrestled with questions of art and sexuality in the gritty New York of the 1970s, won the prestigious National Book Award for Nonfiction.
Smith has said that she is writing a second memoir which she expects to deal with her contemporary life and her later relationship with guitarist Fred "Sonic" Smith.
The book is tentatively titled M Train and is due for publication in late 2015.
Her inquisitive spirit - witnessed in her questioning of religion in Gloria after a conservative upbringing - has even helped her forge a bond with reform-minded Pope Francis.
Smith has performed at both Vatican Christmas concerts under Francis' papacy, most recently singing her pacifist-minded Peaceable Kingdom.
Smith played with both joy and intensity at Webster Hall, performing both her hits such as Because The Night and her lush, melodious cover of Nirvana's Smells Like Teen Spirit, in which the punk icon mourned her late descendant Kurt Cobain not by emulating his anger but by stripping it down.
She announced plans for a new concert on Nov 10 next year for the 40th anniversary of Horses, her debut album often credited as one of the most influential in rock history.
As an audience member blurted out that Nov 10 was his birthday, Smith without a moment's hesitation replied that the date was also the anniversary of the death of Arthur Rimbaud, the French doomed poet whom she considers her artistic inspiration.
But she has not lost her punk passion, ending the show by tearing the strings off her own guitar.
Or her sense of humour. As to whether she has any concerns about turning 68, Smith quipped: "I hear you can still get a guy at 67."