Everything finally seemed to be coming together for John Lennon, as he took the stage for what would sadly become his last public performance on April 18, 1975.

Wife Yoko Ono had become pregnant following their post-Lost Weekend reunion, earlier in 1975; Sean Lennon would be born on John's 35th birthday that October. By then, a New York State Supreme Court judge had reversed Lennon's pending deportation order, allowing him to remain in the U.S.

He'd finally concluded a long-standing legal action over songwriting royalties with his publisher too, and that's what brought Lennon to the New York City's Waldorf Astoria Hotel. The occasion was a gala all-star special, organized for television broadcast, called A Salute to Sir Lew Grade: The Master Showman.

Grade was a master businessman, having outmaneuvered Lennon and Paul McCartney for ownership of their own songs five years before. As they moved into solo careers, Grade ultimately filed lawsuits against both (and Lennon counter-sued) when Lennon and McCartney began sharing songwriting credits with their wives – thus cutting the potential songwriting revenue in half for Grade's Associated Television publishing company.

McCartney ended up winning his case, but Lennon was forced to settle, making ATV the co-publisher of all new Lennon songs in 1974. So, by the spring of the next year, Lennon was on stage to pay tribute to Grade. Well, sort of. Lennon clearly still bore no small amount of ambivalence.

Introduced as "John Lennon Etc.," his band performed with specially created masks from sculptor Ruby Jackson, worn on the backs of their heads. Lennon, who played acoustic while wearing a New York Dolls-style red jumpsuit, reportedly envisioned the masks as a direct reference Grade's two-faced business dealings. "It was a sardonic reference," he's been quoted as saying, "to my feelings on Lew Grade's personality." (The Rutles, a Beatles TV spoof, went even further by featuring a Sir Lew-type character called "Lord Greed.")

Careful television viewers probably noticed the initials "BOMF" on the bass drum, a clue to the Lennon backing group's real identity: They were actually called Brothers of Mother Fuckers, a distinctly un-family friendly moniker that necessitated the more generic "Etc."

Watch 'Salute to Sir Lew: The Master Showman'

Mark Rivera (later of Billy Joel and Lennon's old friend Ringo Starr's band) and a very young Vinny Appice (who would play with Black Sabbath) were part of BOFM, an eight-member amalgamation that earlier provided hand claps for Lennon's No. 1 hit "Whatever Gets You Through the Night." Lennon subsequently convinced the band to change its name yet again, this time to Dog Soldier, after a Lennon-composed lyric for the unrecorded 1975 song "Incantation."

"It was an amazing time," Appice later remembered. "I was going to high school. I was doing that at night. I would hang out with him, and then the next day, I’d be in school, not paying attention." Rivera, by the way, says BOFM's masks had a completely different meaning: “Yoko Ono had us put on skull caps and have a replica of our face," he once said, "to show the duality of American society."

Lennon performed a pair of songs from his then-new album of cover tunes, Rock 'n' Roll, which had just been released the month before – including Little Richard’s “Slippin’ and Slidin’,” and Ben E. King’s “Stand By Me,” the project's lead single. He closed with a new take on the timeless "Imagine," updating it to reflect his recent troubles with the U.S. "Imagine there's ... nothing to kill or die for," Lennon sang, "and no immigration too." He dedicated the song to Grade "and to my other friend, Yoko."

The bill also included Julie Andrews, Tom Jones and early Lennon hero Peter Sellers, performing before a group of Hollywood elite that included Lauren Bacall, Kirk Douglas, Gene Kelly and Orson Welles, among others.

Strangely, the original broadcast which followed in June 1975 left "Stand By Me" on the cutting-room floor, even though it reached the Top 20. That would mark Lennon's last hit, however, before a nearly five-year retirement to raise his son Sean. Lennon returned in 1980 with Double Fantasy, but he was gunned down by a deranged fan before he could take the stage again.

Still, for all of its historical significance, the Sir Lew show has become largely forgotten. Most fans will tell you that John Lennon's Madison Square Garden collaboration with Elton John on Nov. 28, 1974, marked his last live performance. Instead, it was this three-song set.

Grade died at age 91 on Dec. 13, 1998, after a heart operation. By then, ATV had sold the rights to the Beatles songs to Michael Jackson.

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