"Come and Get It" proved to be a pivotal song not once, but twice, for Badfinger. First, however, they had to do it Paul McCartney's way.

Starting out as the Iveys in the mid-'60s, the band was brought into the Beatles' orbit by roadie Mal Evans. Iveys manager Bill Collins had reportedly played in a jazz band with McCartney's dad; Collins introduced Evans to the group. The Beatles then made the Iveys the first signing to their newly formed Apple Records imprint, beginning an initially close relationship.

The name change to Badfinger, in fact, came with the Beatles' stamp of approval, having been derived from the working title for "With a Little Help From My Friends." They initially called it "Bad Finger Boogie," because John Lennon played the demo with an injured hand.

McCartney wrote "Come and Get It," originally for a now-forgotten movie starring Ringo Starr, then held a demo session on July 24, 1969. He approached the whole thing with a steely attention to detail, to the point where even his Beatles bandmates filtered out of the process.

His first take was done with engineer Phil McDonald, during a period when "Come and Get It" was briefly considered for 1969's Abbey Road. He began with a single run through where he sang and played piano, then did a second vocal while playing maracas. Finally, McCartney added drums and bass. He was done in less than an hour.

"Because I lived locally," McCartney remembered in Anthology, "I could get in half an hour before a Beatles session at Abbey Road Studios – knowing it would be empty and all the stuff would be set up."

He presented the original demo to Badfinger a few days later on Aug. 2, then held tryouts before settling on rhythm guitarist Tom Evans for the lead vocal. "Paul asked each of us to sing a verse," bassist Ron Griffiths says in Without You: The Tragic Story of Badfinger by Dan Matovina. "[Guitarist] Pete [Ham] was too 'muggy.' I tried and he said it was a bit nasal, sounded like Reg Presley of the Troggs. Then Tom gave it a shot."

Listen to Paul McCartney's 'Come and Get It' Demo

Tom Evans was told to approach the vocal just as McCartney had. As they rehearsed, McCartney reminded them of every other detail from the original demo, right down to Griffiths' preferred bass sound.

"I said to Badfinger, 'Okay, it's got to be exactly like this demo,' because it had a great feeling on it," McCartney added. "They actually wanted to put their own variations on, but I said, 'No, this really is the right way.' They listened to me – I was producing, after all – and they were good."

Badfinger happily endured this excruciating process, because at this point they were just hoping for a breakthrough. So far, the highlight of their Apple sessions had been 1968's Tony Visconti-produced "Maybe Tomorrow," which stalled at a disappointing No. 67 on the Billboard chart.

"[McCartney] said, 'Look, I've got this song; I've been asked to do the film and I really don't have the time. Do you wanna do it?'" Evans told Glenn A. Baker in 1983. He described McCartney's approach in the studio as "'just copy that, the way it is, and I think you'll have a hit with it,' you know? So, we all learned all the parts on it. We did it in about three hours."

Other than Mike Gibbins' more polished approach at the drums, and a tambourine McCartney added himself, the two takes are virtually identical. Lennon and constant companion Yoko Ono were looking on, at first, as McCartney created this carbon copy. They eventually left, but only after delivering a memorable dig.

"Lennon stopped and looked over at Paul, bowed his head, and said, 'Oh, wise one, oh sage, show us the light,'" Evans says in Without You: The Tragic Story of Badfinger. "The next thing I knew, he walked out the door. I thought, 'Wait a minute, that was John Lennon!'"

McCartney had been commissioned for two other songs on the Magic Christian soundtrack, and offered those two slots to Badfinger, as well. "Carry On Till Tomorrow," which featured orchestrations by Beatles producer George Martin, and "Rock of All Ages" also appeared in the finished film.

Listen to Badfinger's Hit Version of 'Come and Get It'

"Come and Get It" was released in the U.K. that December, and then in January in America. McCartney had been exactly right: It was a hit. By the time Badfinger's single reached the Top 10 in both countries, however, family man Griffiths had already left the lineup.

Tom Evans switched to bass and Joey Molland came on board as second guitarist, but unfortunately more troubles loomed. Badfinger would be riven by awful mismanagement, internal struggles and a series of tragic deaths. They finally broke up in 1975.

Through it all, however, "Come and Get It" remained a bright spot. Evans returned for a 1978 update of the song for K-Tel Records, and that sparked talk of a reunion in the wake of Pete Ham's suicide a few years earlier.

Molland participated in the new "Come and Get It" remake, and he said a spark remained. Evans and Molland eventually returned with Airwaves in 1979, offering a whole new generation the opportunity to experience Badfinger's power-pop joys.

"We didn't actually plan on putting the band back together," Molland said in 2014. "Tom was in London, and I was in Los Angeles. I met a couple of guys, and we started playing together. We were looking for a bass player and I thought about Tommy — but not to put Badfinger back together. Just to play. He flew out and we started writing and playing songs. We thought we ought to try to get a record deal, but we didn’t really have a name. Then somebody suggested we call the band Badfinger. When we sang ['Come and Get It'] together, it sounded like Badfinger. Tommy's voice was so distinctive; you couldn't get that anywhere else. We were sort of talked into it."

Airwaves was followed by 1981's Say No More, before Evans' untimely death a couple of years later. McCartney's initial run through of "Come and Get It" remained unreleased until 1996's Anthology 3. Mike Gibbins then died of a brain aneurysm in 2005, leaving Molland as the lone surviving member from their best-known period.

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