MONDAY

I'm woken at 5am by Lloyd Evans, my writing partner, to warn me about the set of our new play, a trouser-dropping farce set in Buckingham Palace. He's standing in the King's Head, a pub theatre in Islington, and is in such a panic that he's forgotten I'm in North America in the middle of a book tour. "It looks like an S&M parlour," he says. "There's absolutely no way that such a room could exist in Buckingham Palace, except perhaps in the secret locked quarters of the gayest butler they've ever employed." He's extremely worried, not least because the play is due to be unveiled before the public on Friday.

TUESDAY

I'm in Toronto staying at a hotel called The Drake. In between hosting a lunch at "the Groucho Club of Canada" and giving a reading at a nightclub I try to catch 40 winks. I'm about to drop off when I'm interrupted by a blood-curdling scream. What's going on?!? It sounds like someone's being murdered in the next-door room. I creep out into the corridor, armed with a shoe. Almost immediately it happens again. It is coming from the next-door hotel room. Worse, the scream is so high-pitched it sounds like a child rather than a grown-up. I screw up my courage and bang on the door: "Is everything all right in there?" There's a pause, then a woman says: "Fuck off." Seconds later, the screaming starts again, only this time it has an unmistakeable rhythm. Clearly, I've interrupted a couple of sexual deviants. I turn round, and come face to face with the hotel's head of security. "What's going on," he whispers. "I don't know," I say, "but something tells me that's not her husband in there." "It sounds like he's sawing her leg off," he says.

WEDNESDAY

The New York Times publishes a review of my new book - it's being published in America first, then in Britain on 7 September - and against all expectations it's an out-and-out rave. My American editor immediately emails me a note of commiseration. "Your career as a professional failure is at an end," he writes. "I hope you don't take the adjective 'endearing' too hard."

THURSDAY

I arrive back in England to be greeted at Heathrow by my wife and two children. At first I don't recognise my one-year-old son because he's tottering around on two legs. When I left the country 15 days ago he was on all fours. It turns out I've missed my son's first steps. What a terrible hostage to fortune! For the next 50 years, whenever I disappoint my son in any way, my wife will say to him, "What did you expect? He was on a book tour when you took your first steps."

FRIDAY

To the King's Head to see the first preview of A Right Royal Farce. The set is certainly a shocker. With its gold, mirrored surfaces and reams of red velvet, it does indeed have a whiff of an S&M club. But that strikes me as perfect. This is supposed to be a sex farce, after all, not a realistic recreation of life at Buckingham Palace. By the end of the night, even Lloyd has come around. We were worried about being horsewhipped by die-hard Royalists, but the whole production is so incredibly camp it's hard to imagine anyone taking offence. These Royals have clearly sprung from the imaginations of two over-excited schoolboys. If the first preview is anything to go by, A Right Royal Farce is like a cross between Spitting Image and What The Butler Saw. Now all I have to do is persuade The New York Times to review it.

'A Right Royal Farce' runs until 28 August at the King's Head, Islington (020-7226 1916)