Apocalypso Now

The craft steals through the calm of a Caribbean night as silently as a 4 x 100 watt loudspeaker system playing dodgy and distorted salsa allows. Fortunately, the vessel that we dozen Brits had boarded in the Dominican Republic is not the one that is to take us cruising for a week. In maritime parlance, it could most kindly be described as a tender, a launch bearing us across to the twinkling triangle on the horizon - appropriately named MV Horizon.

There is something endearingly British about the way that, each week, a boatload of holidaymakers is despatched upon the high seas to join a Caribbean cruise that is already in progress.

Here's the plan. Celebrity Cruises is a big Greek-American corporation. It sells space on its weekly cruise around the Eastern Caribbean to Britain's biggest tour operator, Thomson. The cruise begins each Saturday in San Juan on the island of Puerto Rico. Unfortunately Thomson's airline, Britannia, does not fly to San Juan. It does, however, fly on Sundays to Santo Domingo.

The good news is that Santo Domingo is a fine Spanish colonial capital, a kind of Havana-which-works, and the perfect place to join a cruise. The bad news is that the most that the British holidaymaker sees of the city is the eccentrically constructed and run international airport. You are decanted from a Boeing 767 into a minibus for the three-hour drive along the coast to closest point on dry land to the good ship Horizon. Then the boat ride begins, scooting noisily across the water to the waiting ship; waiting, indeed, well past her appointed departure time for the arrival of the late-running contingent from Gatwick.

Everyone scrambles on to the more serious ship, each clutching a duty- free bag. Yet our cheap booze is pure contraband, breaking the ship rule that liquor may not be brought aboard. Thus the British stamp their national identity on an otherwise all-American mission.

You meet the rep, Julie - quite the jolliest person in the entire western hemisphere, let alone the Eastern Caribbean.

You meet your cabin steward, whose beaming visage contains only the barest glimpse of disapproval at (a) the duty-free bag and (b) a slightly grubby bicycle.

You meet your room, a bottom-of-the-range- but-perfectly-serviceable "standard inside cabin" that is to perambulate you gently around the Caribbean for a week. And then you become vaguely aware that the ship has started to move, in the general direction of suspended reality.

There are a hundred reasons why cruising is bad for the world, such as the distress and disruption caused to a small island by offloading 1,000 people in the morning for a day-long frenzy of concentrated tourism, only for them to disappear at dusk leaving nothing but a few dollars and a few more dents in a fragile community.

But within five minutes of phoning room service and a fresh salad appearing for supper, and five seconds after illicitly sipping the finest Australian shiraz that Gatwick can sell, you drown out the anxieties by submerging yourself in a foaming bath of excess.

For the first 36 hours of the British version of the cruise, there are none of those troublesome islands to visit. So you idly busy yourself about the ship, establishing routines to support you comfortably for a week. Foraging for sustenance is not among the challenges you face. From before dawn to beyond midnight you could happily pig out in half a dozen venues, then ring cabin service for extra supplies during the small hours. This will cost you not a single penny - or, in the on-board currency, a cent. Horizon most closely resembles an additional US state, drifting without undue purpose off Florida.

Seating for formal dining seems to be allocated by nationality, with British diners kept away from US citizens. So the ideal place to meet Americans is in the men's sauna (though possibly not if you are female). Unless you encounter a strangely reticent specimen, within five sweaty minutes of settling on the painfully piping-hot timbers, you will find out where he is from, how many times he has been divorced, how much he earns - and how much he paid for the cruise.

The one certainty in this torrent of information is that he will have paid more than you. Thomson has negotiated some entertainingly low prices for a five-star cruise. For the peakest of high-season departures, I paid pounds 950. If you were to book the same trip from the Celebrity Cruises' British office, you could pay about half as much again. One benefit of booking direct, though, is that it takes care of the difference between American passengers and the British over tipping. For "difference" read "stinginess".

Celebrity, like many other cruise lines, prescribes the exact gratuity that each passenger should give to various crew members. The idea is to raise wages to a decent level. But the practice finds little favour among some Thomson passengers. As Horizon sailed south of the Puerto Rico Trench, discontent was marked by an unseemly mutiny: the tip envelopes of some Brits were a good few notes short of the appropriate wad of dollars. For direct clients, Celebrity avoids financial embarrassment by issuing tipping vouchers in advance - removing the voluntary element from the equation.

Whatever the staff in the Starlight Restaurant earn from the British, they deserve double for unflagging good humour and service. The set piece each day is an elaborate dinner, such as is served in the kind of restaurant that would not normally have to cater for people like me. Another aspect that takes some getting used to is that you share a table with the same diners every night. You have seven opportunities to become accustomed to the idea, by which time the petits fours have multiplied to grands vingt-huits and you have not a snowflake-in-a-sauna's chance of sweating off the excess weight. Luckily I found the Knox family from Yorkshire unstintingly entertaining, though they might not say the same about me. Five stars for this family of five, then, but none for the official on- board entertainment: a dreary procession of sub-Broadway pastiches that would never have made it to Butlin's at Bognor Regis. But unlike Butlin's, you can quickly escape to the deck to watch a full moon drench quicksilver upon a thousand islets in the mirrored sea.

Ah yes, that's where we are - the Caribbean, threading through a necklace of islands which enjoy the possibly dubious and certainly temporary benefit of our company. Names skip enticingly from the pages of the brochure as if you were flicking through a stamp album: Antigua, Barbados, Martinique, Puerto Rico, St Thomas. And some people's view of the ports-of-call is as two-dimensional as a postage stamp. As far as the ship's excursions desk is concerned, the perfect passenger is expected to sign up for a minibus trip around the island, eat a mass-produced lunch and end up at a mass-produced souvenir shop.

Yet you can easily evade expectations. The charter airline will accept a bicycle for free. It stows neatly into your cabin without impeding the procession of room service deliveries. You are now equipped for rapid transport around the ship (there may be a by-law prohibiting on-board cycling but I swear I never saw it). And with two wheels you are able to glide effortfully around each island, taking stock of the scenery and providing modest entertainment for the local people - especially when hauling yourself wheezily up the little-known Barbados Alps. Take the cycle clips off on Martinique, the insufferably jolie French island with Himalayan tendencies; next day, pedal thankfully across Antigua's ample acres.

St Thomas is the saddest call: handsome Danish heritage swamped by a tidal wave of tawdry daytrippery. Conserve your calves for Puerto Rico, big and pretty enough to absorb its role as the Clapham Junction of the Caribbean cruise. At the boistrous harbour in San Juan, you bid farewell to your sauna-soulmates - who miss out on the best treat of the whole voyage.

While Chuck and Hank fly back to the Midwestern snows, the British enjoy the longest stay of all: 16 hours in one of the minor gems of the Spanish Caribbean, inhabited by a raucously friendly bunch of people with apparently no business more pressing than to exchange beers with British boaters.

The final night leaves you in an unfamiliar position of seniority. To the new arrivals who boarded in Puerto Rico, you are an old shiphand, demonstrating your grasp of the ropes (and the sauna) to the newcomers. How curious your departure must appear to them the next morning when Horizon moors off the Dominican coast. A mobile juke box puffs across from the mainland to pick up that funny lot, still defiantly clutching their duty-free bags.