I’m not a seafaring person, and I didn’t think I was going to like it,” admits Zoë Ball, recalling how her husband, Norman Cook, aka DJ Fatboy Slim, had some difficulty convincing her that they should buy Barracuda, a 100ft yacht that was used as a German spy boat in the second world war. “I couldn’t say, ‘I hate boats,’ when Norman told me about it, but after a dodgy experience in the Seychelles, I did fear that feeling of claustrophobia.”

That’s the problem with boats: lovely when you’re lying on deck, but not much fun when you’re banging your head on the way back from the bathroom at night. As they are both tall, the couple needed to undertake a user-friendly refurb, so they called in a designer. The yacht now has four good-sized cabins, and gets rented out when the pair are not using it. And as for Zoë’s input? “She just swans around, drinks champagne and invites friends to enjoy it,” Norman says.

Unsurprisingly, music is an essential part of the Barracuda experience — a fully loaded iPod holds customised playlists and is linked to club-quality movable speakers. “Like all DJs, I watch the crowd,” Norman says. “Loud house or rock doesn’t seem to fit — you need it more atmospheric and filmic, especially at sunset.”

Among those to sea-test the soundtracks have been Kaiser Chiefs, Arctic Monkeys and Carl Cox. “We’ve got loads of playlists — chill-out, party and wild card, which has crazy stuff such as Singing in the Bathtub by Robert Crumb and rare blues tracks. We even have a tea-dance playlist for my parents, with 1940s records.”

Still, the music was probably the cheap part. The Barracuda is now a plush water palace anchored off Sardinia’s Emerald Coast, but it has taken about £2m to get it there. “We called it a refit, but actually the boat had to be rebuilt,” Norman says. “Whatever you think something like this will cost, however long you imagine it will take — double both.

“We wanted it to be anything but a bog-standard working boat,” he continues. “There are bathrooms rather than heads, there is a kitchen instead of a galley, and it’s all as homely as possible. We didn’t want a gin-palace superyacht — we wanted something funky.”

In fact, it was a chance for the couple to interpret what they liked about staying in hotels. “We wanted things you wouldn’t expect on a boat — Cowshed products, decent-sized cupboards and a kitchen where you can sit with a glass of wine, watch the chef and get involved,” says Zoë.

Unsurprisingly, a holiday with Brighton’s coolest couple is one long party, fuelled by on-tap rum punches and bubbly. “I’ve noticed that, after a few days, the stewardess starts watering down the cocktails,” admits Norman.

A favourite on board is the dressing-up box, which gets plundered alarmingly often. “Barracuda has given me a few scares over the years, but seeing my son, Woody, dressed as a pirate on deck was the moment it stole my heart,” Zoë says. “When you’re lounging around, sailing at sunset, you look up and think, ‘Wow, this is our boat.’ That feels pretty amazing.”

As well as going to sleep in one secluded cove and waking up in another, the allure of the boat is its exclusivity. “As in a villa hidden up in the hills, you have total privacy,” Norman says — it’s something the couple cherish. “You can shout loudly, drink as much as you like, horse around and nobody can see you. That’s more relaxing than sharing a place with other guests.”

Best of all, their memories stay private. “The paparazzi have got us on pretty much every holiday, except on the boat,” he says. “And no, that isn’t a challenge to them.”

Hire Barracuda for £20,000 a week, all-inclusive (transfers included, not flights); 0845 034 0700, www.smithandfriends. com/barracuda . The yacht is moored in a marina in Portisco, northeast Sardinia, a 20-minute drive from Olbia airport

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