Rob Grant is shaking his energy drink can at me by way of explaining that we don’t need coffee. “I’m on my third Red Bull. Any more and I’ll have a heart attack,” grins the 70-year-old self-anointed “nepodaddy” to Lana Del Rey. With or without caffeine, the sailor-meets-Floridian-man-about-town is a seemingly inexhaustible source of renewable energy. As a dad-in-demand, this is convenient: while he’s sat in the podcast room at Rough Trade East for our interview, his phone near-constantly dings with messages, and that’s after three hours’ worth of fans who queued up to briefly meet him and get their copies of his debut album, Lost At Sea, signed. This is all exciting and he’s grateful but just as captured on his album cover – him on a moving boat, face and body open to the sun – he’s taking it in his stride.

It’s the Grant family weekend in London. The girls and gays are out en masse in Hawaiian shirts for Rob and white lace dresses for Lana, as per her Lolita-meets-Old Hollywood style. Everyone seems to be doing the double whammy of events: meet Rob here, then head over to Lana’s British Summer Time show at Hyde Park. It’s the same trail Rob will be taking: leaving shortly to watch Lana from side-stage and post videos of the set online for their shared adoring fans.

In the queue outside, I met Emma, who had travelled down from Glasgow in her official Lana merch racing jacket for this. “If you close your eyes and listen to his piano playing, you feel the waves,” the 25-year-old told me. “If it wasn’t for Lana I wouldn’t have found his album… but if it wasn’t for him there’d be no Lana. I think it’s beautiful that a father and daughter can both express themselves separately and together through music.” Others echoed this vision of Rob’s new music as an expansion of the Lana cinematic universe. Emily, a 23-year-old from London said, “Being a Lana fan, knowing Rob comes hand-in-hand. He’s always been in her pictures and referenced in songs. It’s nice to finally get to hear his music and get his perspective on their story and who he is.”

Grant grew up in Rhode Island on the east coast of the States. He played the piano for fun but preferred writing and composed short stories like his literary heroes Ernest Hemingway and F Scott Fitzgerald, and poetry in the style of TS Eliot. After winning a couple of small awards for his prose, he thought if anything he’d be a writer over a musician. But this picture of his childhood is deceptively quaint. “I’ll tell you, I was also honestly a juvenile delinquent. I was a bad boy. I really was,” he says. “I was constantly getting into trouble.” Everything changed when he was given a boat at age ten. “It kind of took all that negative energy away, and I was able to focus now on the ocean. And I would sail alone, and I'd be out off the Atlantic coast. Hitting Nantucket Island, Block Island, Martha’s Vineyard.”

That sense of adventure carried him through his surprisingly varied and eclectic working life: “I’ve had restaurants, boat-building companies, rustic furniture, advertising, the internet, real estate. And a lot of them I still have,” he says, waving each venture across an imaginary sea with his hand. He made his start in New York City in his twenties working at the prestigious Grey Group advertising company. Playtex was one of their accounts and they had just discovered a new niche in bras. “Are you ready?” Grant asks. “For women who didn’t have huge breasts. And those gals had to go down into the basement of the department stores and claw around in these bins, right, for these bras. They could never find what fit. So, the strategic selling point was fit, right? I'm sitting at my little desk as a junior copywriter. And it’s nine o’clock at night and everybody’s gone home. And I wrote the initials ‘T G I F’ and under that I put ‘Thank Goodness It Fits’. And I knew this was going to be a big idea. I waited until that next morning, and then I put the piece of paper underneath my creative director’s nose. He wasn't ready for it. He looked at it – jumped up! And that ultimately became a 500 million dollar campaign for Playtex. Right away they gave me a beautiful office of glass overlooking New York City. And that’s how my career started.”

The unifying force through all his work is a sharp instinct, an innate ability to be just ahead of the zeitgeist. When he got into bulk-buying domain names in the mid-90s, there were no search engines. “Think of that – no Google, no Yahoo, nothing,” he remembers. “And my hunch was that people would begin to search intuitively. So if you were interested in tropical fish, you type in tropicalfish.com.” Anything he could think of, he bought. “I had to register and then hold these domains and pay the renewal fees for, I’d say, seven or eight years before any of that got validated. And I think it was 1999, The New York Times ran a big article on the sale of wallstreet.com for a million bucks. And that’s when the floodgates opened. And that’s when I knew my hunch was correct. It became a gold rush after that.”

Writing and releasing an album of music was just another unusual career turn for those who know him. He’d co-written “Sweet Carolina” on Lana’s 2021 record Blue Banisters and when they were recording that album, Lana was typically a few hours late to the studio. Rob was on time and told the producers to record him while he improvised piano for 75 minutes straight. They were gobsmacked. Rob sent the audio on to Lana’s manager, Ben Mawson who started shopping it around and got him a deal with Decca Records. Lana’s producer extraordinaire Jack Antonoff and ambient composer and producer Luke Howard helped Grant cut up the improvised recordings into tracks and finish a full debut.

The result was the 40 minutes of relaxing wellness music on Lost At Sea. Two of the songs – the title track and “Hollywood Bowl” – feature Lana’s vocals overlaying his soft, mystical piano playing. Fans are using it for meditation, to fall asleep to and to start their day with, journaling and drinking tea. Interestingly, Rob doesn’t read music. “If you were to hold up sheet music now, I couldn’t tell you, it’d be like Martian. The music is entirely by ear and very intuitive,” he explains. “People often say, ‘Well, how do you feel about not having any kind of classical training?’ I feel like it’s very liberating. I can do no wrong, right? Because I don’t know enough to do wrong. It’s all just coming out of me.” Would he feel restricted if he retroactively learned to read music now; would it take something from his magic formula? It would, he replies. “First of all, I hate any kind of structured environment. I hated school. Honestly, I hated the corporate world when I worked in advertising. I’m very much a free-flow, entrepreneurial, opportunistic kind of guy. That’s where I flourish. So if you told me now, I was gonna have to take piano lessons I’d shoot myself. Honestly. It’d be my worst nightmare. I love the fact that I don’t know what the parameters are.”

Maybe this rubs people up the wrong way, he says, along with the fact he has a famous musician for a daughter. For example, he went to a little party in Florida, where he lives, and one of the guests was a classically-trained pianist. The pianist invited Rob to play the piano, so he did, in front of everyone. “I later learned he was so confused because the music was beautiful. But he knew I had no training. And I think it was honestly very disconcerting for him. And I get it. Here comes Rob, right? He sits down, plays these songs, and gets a deal with Decca. My condolences.” He smiles broadly.

It’s the water that Rob loves so much that guides the music. When he sits at the piano, he can immediately visualise what it’s like to be riding the waves. “I’m always out there chasing sharks and all kinds of critters. And I let them all go when I catch them, but I’ve been working my way up the food chain and now I’m targeting these huge tiger sharks and bull sharks so big they’ll tow the boat. The last shark I caught was 12 feet long, and towed the boat for about two hours. And so the music just meshes. It’s very natural. If we had a piano here, and you asked me to play, I wouldn’t know what I was gonna play for you. It’s really interesting, very mysterious, where it comes from.”

The mysticism is something that mirrors the spirituality inherent in Lana’s music. Does he consider himself a spiritual person? “I am in the sense that I love nature and I find great peace in being alone out on the ocean, or for that matter on a river. Or in the woods,” he explains. “Am I religious? No, not in the traditional sense at all. But for me, you know, it’s all about nature. And I think really, you can learn pretty much everything if you just watch nature. So in that regard, we’re all wondering where we came from, and where we’re going and what the universe is and the meaning of life…and I won’t pretend to be able to tell you, but I think we all find peace somewhere. And for me, it’s nature. Others find it in religion or philosophy. I could never buy into any of the traditional religions. I mean, I love Buddhism, I think that’s very profound. But nothing makes me happier than being out on the ocean.”

He already has a second album’s worth of music ready to record and release later in the year or next year. “You’re the first to know that,” he says, and to know that he’s worked on more music with Lana. That’s what’s been the highlight of all this for him: working not only with his eldest daughter on music, but with his other kids: his daughter, Chuck, who shot the album artwork and campaign photography, and his son Charlie, who helped with the music video shoot for ‘Lost At Sea’. “It’s really been a family affair. In this day and age, it’s kind of a happy little fairy tale,” he says.

By the time his children were two years old, he saw the creative spark in each of them. “Lana was singing before she could walk honestly. Totally innate,” he recalls. “Fathers come up to me, who’ve got daughters who want to go into the music biz: ‘What’s the secret?’ I say, there is no secret. Either your kid has got talent, and has got unbelievable ambition… and it takes delusional thinking, in my opinion, where no matter what people tell you, you never stop. You just keep going forward. Lana Del Rey epitomises that. Caroline’s got a gorgeous voice, Chuck. She did a lot of school plays when she was young, we’ve got all the old VHS tapes. I mean, you should hear Chuck’s voice. But she went in another direction. She went into photography, and then Charlie: Charlie’s very smart, very creative. And I think Charlie’s still kind of searching. He’s the youngest.”

They’ve been supportive of Rob’s new musical ambitions. “And I’m sure it’s odd to have your father coming out with an album at 70. I recognise that it probably creates some awkward situations, but they’ve been great. They’re all very philosophical about it all. Like: where’s it going to take us? Hard to say. And it’s scary. It can be really uncomfortable. I mean, pretty much everything I’ve done has been way outside my comfort zone. But look where it brings you. A lot of people my age, they’re out there playing pickleball and that’s pretty much it.”

That’s like bowls, right? Boring, I say.

Rob nods and shakes his head gravely at the same time. “It’s kind of what they all end up doing. Now, I’ve got nothing against pickleball. It just goes hand in hand with the early bird specials and all that shit. For me, I’d rather die on the boat catching a shark or recording music. That’s the path I’m gonna take. And I’m gonna hopefully stay young and be able to keep pursuing it.”

Rob Grant’s debut album Lost At Sea is out now