‘Seeing it’s Thanksgiving, we thought we’d make tonight a little bit of a joyous occasion by inviting someone up with us onto stage. I’m sure he’ll be no stranger to anyone in the audience … It’s our great privilege and your great privilege to see and hear Mr John Lennon …’

I’ve heard some spine-tingling roars from concert crowds over the years and been in the thick of some extraordinary atmospheres. Those early Beatles concerts, with the teenage girls going wild to the point where you couldn’t hear yourself think. The Stones at Hyde Park. Nina Simone at Annie’s Room, with her staring down the diners who dared to eat while she sang. Later, I’d witness Elton John at Dodger Stadium. Mick Jagger and Tina Turner at Live Aid. The Rolling Stones in Argentina. But even among those many remarkable memories, there was something unique about the November night in 1974 when John Lennon walked onto the stage at Madison Square Garden to play with Elton.

The Garden has always been one of my favourite venues. It has amazing acoustics, with a cleverly designed concave ceiling that helps to capture the sound. This structure is suspended from above with a network of steel cables that allows everyone’s view to be unobstructed. All of this means that when something magic happens, the Garden properly, literally rocks. That night, when John Lennon came on stage as I watched from the wings, even the limousines were bouncing in the car park.

John strode onto the stage with that unmistakeable swagger of his. His black and white Telecaster guitar matched his outfit. He was head to foot in black, with just a white gardenia pinned to the centre of his shirt and a sheriff’s badge glinting in the spotlight. His long hair was a rich shade of brown, his sunglasses that familiar pair of small black circles. He exuded stardom, looked every inch the star.

Elton rose from his piano to greet him. His glasses were as large as John’s were small. He’d been wearing a sort of two-piece jumpsuit, white and studded with sequins. By this point in the concert, the jacket had long gone and he was bare-chested, bar the sparkling pair of braces that were holding up his trousers. Elton was as big a star as you could get. Goodbye Yellow Brick Road had been released the year before and had dominated the radio airwaves ever since. As John passed, Elton gave a sort of half-bow, half-curtsey, patted John on the back as he walked to his microphone, then led the crowd in the continuing applause.

Maybe it was the combination of Elton being the biggest act on the planet and the rarity of seeing John on stage that made that welcome so overwhelming. John hadn’t performed in public for years, and as events would transpire, he’d barely do so again. While all the other Beatles had enjoyed number ones with their solo work, John had found it harder to cut through with his material. His politics and the clashes with the American government of the time had made him a controversial figure in some parts of the media. But that night, the affection in the room, the love for him, was unmistakeable.

The applause continued. It rang round the Garden in waves, surging through the audience, giving me goosebumps. Elton glanced over to where I was standing. He was laughing, as if to say, ‘This is going well, isn’t it?’ I had a lump in my throat and was clapping, smiling and nodding back. Elton and I both knew how much it had taken to get John up on stage. I felt an immense swell of pride as I stood there, and I still cherish the knowledge that I was involved in making what became one of the iconic moments in music in the 1970s happen.

The link between Elton and the Beatles went back to when I was working for George Martin’s AIR Music in the second half of the 1960s, promoting the various acts he was recording with. When I first started working for AIR, there wasn’t room for me in their main office in Baker Street, so they found me a space at Dick James Music (DJM, as it was known). Dick was the publisher of all the Beatles’ music, so he had a close relationship with George. He was a lovely guy, friendly and kind.

On the front desk at the office was a girl called Charlotte, who when she wasn’t answering calls used to make necklaces – beautiful long strings of love beads. Even now I still have some of them in a jar at home. On one occasion, Dick was having his weekly progress meeting, which I was meant to attend. But while I’d been talking on the telephone to some radio or TV producer, I’d been wearing and playing with some of Charlotte’s necklaces, and they got all tangled up in the phone cord. As I put the phone down to go to the meeting, I realised I was completely entangled. I turned up at the meeting ten minutes late.

‘I’m sorry I’m late,’ I said to everyone, ‘but my necklaces got caught up in the phone.’

Everyone fell about laughing, and that line became an office catchphrase. After that, every time I was late for anything I was asked if I’d had another necklace mishap.

It was at Dick James’s office that I first met Elton – or Reg, as he was at the time. He was fantastically shy back then, wouldn’t say boo to a goose. He didn’t seem at all like the person who’d be charismatically wowing audiences in a few years’ time; he was kitted out in a jean jacket and jeans – double-denimed, if I remember correctly. The two of us couldn’t have looked more different. In his autobiography, Elton said that I could have drawn attention to myself even during a Martian invasion. I was certainly quite out there when it came to fashion: as well as my love beads, I had a thing for antique silk scarves at the time, and I often wore velvet trousers and had streaks in my hair.

I could tell as we talked that Reg was quite taken by my appearance. He was a musician looking to make it, and the fact that I was working for George Martin and had previously worked with the Rolling Stones made me someone he wanted to know better. And as I got to know Reg himself, it quickly became apparent to me how much he knew about music, which left me thinking, This guy really knows his stuff. We immediately developed a firm friendship, and I did what I could to put work his way, to help him get that first foot on the ladder. Reg became a regular at the office, and that’s where the Beatles link began.

Fast-forward to the mid-1970s, and Elton was offering a helping hand to John Lennon. On John’s 1974 album Walls and Bridges, Elton appeared on two tracks, playing Hammond organ and singing background vocals on ‘Surprise, Surprise (Sweet Bird of Paradox)’, and playing piano and singing on what would become the album’s most successful single, ‘Whatever Gets You Thru the Night’. The inspiration for the latter came from John channel-surfing TV late at night. He had come across a Black evangelist preacher, Reverend Ike, who had told viewers, ‘Let me tell you guys, it doesn’t matter, it’s whatever gets you through the night.’ John loved that phrase and wrote it down in one of his many notebooks.

According to some accounts, the song took its original feel from ‘Rock Your Baby’ by George McCrae, which was a big hit at the time. Once John and Elton had recorded their parts at Record Plant East, ‘Whatever Gets You Thru the Night’ morphed into this pulsating potential hit, Elton’s piano and John’s guitar chinking and syncing in time, the bass rippling up and down underneath, with this delicious, dirty 1970s sax threatening to burst through the speakers in between the singing. Jimmy Iovine, who engineered the sessions, later said that ‘John knew what he wanted … he was going after a noise and he knew how to get it.’ ‘Whatever Gets You Thru the Night’ is one of those songs that is both of its time and somehow timeless as well. The freshness and the energy of the recording is still clear today; it’s three and a half minutes of joie de vivre.

The story often told is that Elton and John had a bet in the studio: if ‘Whatever Gets You Thru the Night’ got to number one in the American charts, then John would appear at Elton’s Thanksgiving show at Madison Square Garden. That’s not quite my recollection. For all its immediacy, the song wasn’t even going to be a single originally; it was only thanks to some twisting of arms by the record company that it became the first track released from the album. As I recall, Elton just wanted John to appear at Madison Square Garden with him. I was looking after John at the time, so Elton asked me to ask him. When I spoke to John, he wasn’t sure at first. At this point, he hadn’t played live for a couple of years, but he came back with a condition: only if ‘Whatever Gets You Thru the Night’ got to number one would he join Elton on stage. I think John thought it was a safe bet that such a thing would never happen. His last single, the title track from his previous album, Mind Games, had only made it to number eighteen on the Billboard charts.

John, though, hadn’t reckoned for the promotional push of having Elton on the record,...