In the throes of his "Lost Weekend" period, Lennon was in a Los Angeles studio overseeing production of Harry Nilsson's Pussy Cats album. Present were a number of players � including Stevie Wonder, guitarist Jesse Ed Davis, saxophonist Bobby Keys and Nilsson himself. McCartney was accompanied by his wife, Linda. Lennon's then-girlfriend, May Pang, was there as well.

"We had no clue he was coming," said Pang, referring to McCartney's visit in Peter Ames Carlin's recent McCartney biography, McCartney: A Life. "All of a sudden we turned around, and Paul was there."

So began the only instance in which, post-Beatles, Lennon and McCartney ever joined forces in the studio. Remarkably, although Pang had made reference to the event previously, it wasn't until May 1992 that McCartney confirmed that the studio reunion had occurred. "It's very difficult to remember those days, because it was all a bit crazy and everyone was getting out of it," McCartney revealed. "But yes, John was doing some recordings in Los Angeles and I showed up."

Indeed, the night was late, the day's "official" sessions were complete, and, by all accounts, the gathered musicians � including Lennon and McCartney � were, to varying degrees, in chemically-induced altered states of mind. Disappointed he had missed the session, McCartney edged toward the drum kit, where Ringo Starr had been sitting earlier, and picked up the sticks. "Ah, okay," Lennon said, looking around for his guitar. "Maybe we'll have a little jam."

As detailed by Carlin, Linda then seated herself at the organ, Wonder manned the electric piano, Jesse Ed Davis picked up his six-string, and a musician from a session next door strapped on a bass. Lennon began ad-libbing some vocals, and Wonder launched into a gospel-style progression that evolved into a funky version of "Lucille." "Stand By Me" came next, with Lennon, McCartney, and Nilsson sharing vocals. Pang later recalled that the ad-hoc group also pulled together a skiffle rendition of the Leadbelly classic, "Midnight Special."

The session sputtered on into the wee hours, but technical problems were rampant, and Lennon became progressively irritable. Still, in the words of Pang, the Lennon-McCartney reunion "was like yesterday � they didn't skip a beat, just went right into it."
Even more enticingly, although Beatles fans never knew, the spontaneous jam session very nearly sparked a full-on Fab Four reunion. The day after the jam, at Lennon's invitation, McCartney, Linda, and the couple's children went to Lennon's rented Malibu home. Gathered around the pool were Ringo, Keith Moon and a handful of others. Lennon soon joined them. McCartney sat at a piano for most of the afternoon, playing Beatles songs and some standards. Ringo seated himself on the bench next to McCartney, singing along and having a rollicking good time.

As day turned to night, Lennon and McCartney bid their adieus. "Let's see each other again," McCartney said. Lennon nodded in agreement. Afterwards, Pang overheard Lennon tell Nilsson, "Wouldn't it be fun to get the guys back together again?" In the minds of Nilsson and Pang, there was no doubt which "guys" Lennon was referring to. Some might dismiss Lennon's remarks as whimsical musing, but years later, in an interview with Earcandy magazine, Pang insisted otherwise.

"He wanted to write with Paul again," she said. "He asked me if I thought it was a good idea. I told him I thought it was a great idea. Solo they were great, but together they were unbeatable. He thought about it and he said, 'You know what? Let's go down and visit Paul and Linda.'"

The proposed visit was to take place in early 1975, in New Orleans, where McCartney was working on Wings' Venus and Mars album. Lennon was back in New York by then, still living with Pang. Just before the trip was to be arranged, Yoko Ono phoned Lennon, insisting the stars were aligned for him to undergo a smoking cessation program. The trip to New Orleans was postponed, and was ultimately abandoned altogether.