This is no ordinary train. This is the Can-Can Express. It is an oddly chosen name for a train that left Calais almost three hours ago and has been travelling only a little faster than jogging speed ever since. And whatever it is that they're doing in the bar/disco carriage, it certainly isn't the cancan.
We shudder to a halt at a level crossing. The Pet Shop Boys don't. A woman in an apron looks up from her vegetable garden at our gyrating train: 'You are always on my mind, you are always on my mind.'
It costs from pounds 29 to pounds 39 (depending on the time of year) to go to Paris on the Can-Can Express. The price includes the ferry crossing, the trip on the charter train, two Metro tickets and a map. The bad news is that, having pulled in to Gare St Lazare at 4pm (5pm with delays), you must return to the train, Cinderella-like, by half- past midnight for the slow rumble back to the port. The even worse news is that you have to leave the train at Calais at 6am.
But the French Travel Service, which runs the new operation, is not short of ideas about how travellers on the Can- Can Express might spend their time in Paris. Aside from offering excursions to the Lido and around the city by coach or bateau-mouche, they maintain that it is possible to pack in three or four hours at Euro Disney, if you move at lightning speed to the RER train connection. It is also suggested that visitors may wish to 'mix with students of the whole world in the Latin Quarter and discuss philosophical topics while enjoying a very affordable meal'. Excusez-moi] Cheap steak-frites may be on the menu, but when was the last time you had a chat about the causal theory of perception over pudding?
In fact, we had time for shopping in Paris and then a delicious pounds 20-a-head dinner in a philosophy-free restaurant before beginning to worry what the journey home would be like. The bar/disco carriage promised, after all, to stay open all night. Would there be congas in the corridors? Capers in the compartments? Would the Lycra girls try to join the six- foot-high club in one of the loos?
Boarding the train at 12.20am, the first signs were not good. As we opened the door, a big bloke with a ponytail lurched forward, clutching a bandaged hand. 'I'll be OK,' he said. 'It just needs a couple of stitches when we get home.' Our first thought was that the four barmen-cum-bouncers - amiable giants in 'Can-Can' T-shirts - might soon be wanting three falls or a submission from some of the passengers, but thankfully this was not the case.
Most of us, goody-goody-better-take-a- brolly-in-case-it-rains sort of people, were content to sit in the semi-darkness of the regular carriages and wait for the worst. Many tried to sleep in various classically uncomfortable arrangements. They tried the Bookshelf, bodies leaning at the same angle against the window; and the Spoon Drawer, where you lift the centre arm and make a tight figure 'S' with your neighbour. Some tried the uncompromising Toolbox position before giving in to the Mangle, a hopeless freestyle jumble of legs, bottoms and lolling heads.
Jean Bernardi, whose idea it was to run the Can-Can Express, has carefully calculated the equation of discomfort and low cost. He is confident that twice a month at least 300 passengers will deliver themselves to Dover for a day trip by train to Paris. Mr Bernardi is married to a Scot. He says that if people from his wife's village near Dunfermline, Fife, are prepared to spend two nights on a coach for the sake of a few hours in Boulogne, then this relatively agreeable journey must be a winner.
Certainly, in comparison with long hours on a coach, our train felt more like the Orient than the Can-Can Express. And I can almost imagine getting a group of friends together for a night in Paris and enjoying both that and the occasional grimness of the journey.
What the Lycra girls wrote in their diaries afterwards is impossible to speculate. The early headbanging promise of the bar and disco was cut horribly short when, by accident or design, the tape machine broke down soon after we left Paris. Faced with singing their own versions of Guns N' Roses' biggest hits or sipping in silence, the party people stirred to a dimly remembered childhood instinct: they rolled up their sleeves and played charades all the way to the English Channel.
Further information: The French Travel Service (081-742 3377) is running its next Can-Can Express trains on 3 and 17 October. The costs is pounds 35, with first-class seats available for a supplement of pounds 8. A coach tour of Paris costs an additional pounds 15; a bateau-mouche trip costs pounds 4 ( pounds 54 with dinner). London to Dover by coach with National Express is pounds 10 return.