So, a couple of weeks later, after catching a connecting twin-prop from Antigua, I found myself in a rented open-top 4WD, nervously negotiating the precarious road that led from the airfield to the isolated north of the island. I needn’t have worried. By the time I’d arrived at our destination, Portsmouth, the old capital of the island, I’d seen two European faces and scenery I’d never thought possible in the Caribbean.

A beautifully rugged coastline and the lack of pristine white-sand beaches have managed to keep the mega-resort hordes away. Not that they haven’t had a go at attracting visitors. There’s a great book called 100-Plus Things to Do in Dominica. Unfortunately, tip No 88 suggests you “go off island”. This comes straight after No 87, which proposes you “do nothing”. Maybe they should have stuck to 50 Things to Do.

One of the reasons for the suggested exile might have been the headline in the local paper, the day I arrived. It read simply: “More gays coming!” There was great concern that gay cruise ships were going to dock in Roseau, the island’s capital, offloading their techno-hungry cargo on a nervous population. I tried to look as hetero as possible in my tight Speedos.

Portsmouth itself is a sweet little ramshackle town with three or four good restaurants and a couple of good seafront bars. Not that you need to eat out. Dominica is a veritable horn of plenty. Everywhere you look, trees groan under their loads of guava, passion fruit and pineapples. Just negotiating the 200 yards from bed to beach involved walking on a solid carpet of fallen mangoes worth at least £300 on the Portobello Road market. Nobody goes hungry in Dominica.

My first night in town coincided with the wrap party for the current section of filming of Pirates of the Caribbean. This was definitely a special evening for this sleepy little town, and “le tout” Portsmouth turned out, dressed up to the nines. I was possibly still a little jet-lagged and suffering from the effects of a couple of large rum punches.

I challenged Johnny Depp to an arm wrestle, bored Orlando Bloom to death about how great it was to get away from Blighty, before pitching my new movie idea to uber-producer Jerry Bruckheimer. It was actually going quite well until I had to go and throw up in a bush. He wasn’t there when I came back. I’ll call him; we’ll do lunch.

I pretty much spent the next five days underwater. I swam with stingrays, frolicked with turtles, followed shoals of multicoloured fish through magical tunnels and pristine coral arches. It felt like I was living in some perfect aquarium. The moment your body hits the water, topside worries just disappear: bills to pay, lives to lead, things to do. You just want to stay underwater for ever, maybe evolve and grow gills.

We all have a friend who opts out of the rat race and does his own thing, and everyone kind of tut-tuts and mutters about irresponsibility and uncertain futures. I hate to say it, but I think that we just might have it all wrong. Go dive, change your life.

Travel details: Dom Joly travelled as a guest of Caribtours (020 7751 0660, www.caribtours.co.uk), which has a week, room-only, at Fort Young Hotel from £855pp (two weeks from £1,010pp), including British Airways flights from Gatwick to Antigua, connecting flights to Dominica and transfers. Connecting flights from UK regional aiports are free. Caribtours can also arrange a two-tank day dive for a qualified diver (£37) or a five-day Padi open-water course (£213).

Other operators include Harlequin Holidays (01708 850300, www.harlequinholidays.com), Trips Worldwide (0117 311 4402, www.tripsworldwide.co.uk) and Virgin Holidays (0870 220 2468, www.virgin.com/holidays).

For further information, call the Dominica Tourist Board on 020 8350 1004 or visit www.dominica.dm.

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