The mission: Maggie O'Farrell tries to find out what the future holds - shame no one warned her about Kevin Kline

rophecies and predictions, I've always believed, are the territory of the mad and/or pathologically bored. And why would I want to know what's going to happen to me next week? I don't, after all, have to wait very long to find out. I also suspect it's a slippery slope: it may start as a harmless peek at your horoscope, but before you know it you're a crystal- carrying nutter frightening everybody with your talk about auras. But I decide - for one week only - to throw trepidation and scepticism to the heavenly spheres. I will believe the predictions and live accordingly.

I approach the world of my future with caution, which rapidly degenerates into confusion: "Move quickly," a women's magazine urges, "details may be scarce, but you mustn't wait." The whole thing seems to rely on making ridiculous and unspecific statements that can be subject to any interpretation you fancy.

When I visit Magda, a tarot-reader with ill-fitting dentures and star- sign wallpaper, she says: "Beware of being the Healer. Make a transition to the Warrior. Thursday could be an important day for the beginning of a spiritual union." The palmist, meanwhile, strokes my thumb for an uncomfortably long time and then tells me that Wednesday may bring "an amount" of money.

I make a vague Faustian pact with some divine being or other that if it all comes true I'll rush out and buy a crystal and never, ever take the piss out of horoscopes again.

Monday: begin the week by moving quickly. Unfortunately, any semblance of velocity isn't easy to achieve on a crowded escalator and I trip on my Birkenstocks, one of which flies off and strikes the woman ahead of me in the back of the calf.

Tuesday: am moving less quickly owing to ankle injury sustained in Birkenstocks/ escalator incident.

Wednesday: hobble to the doormat to see if any unknown benefactors have sent me a cheque for a million pounds. Find instead a letter saying my council tax has been miscalculated and I owe an extra pounds 100. Furious, I grind the letter up in the waste disposal unit and denounce the palmist as a charlatan. In the afternoon, my father calls. I perk up instantly, wondering if he's about to say, "Your mother and I are re- mortgaging the house and disinheriting your sisters. It's all yours." But, instead, he harumphs about the weather and asks me if I've ever read any books on 19th-century Edinburgh.

Thursday: not entirely sure I want a spiritual union, partly because I don't know exactly what it is. Does it mean sex or no sex? I didn't like to ask. Through the day, I come across a bus driver with stains down his front, a man in an annoying jester hat and a bloke playing a banjo badly outside Boots. Denounce the tarot reader as a fraud. But in the night I dream I'm marrying Kevin Kline.

Friday: oh my God. Am I destined to become a Hollywood wife? This is horrible. I don't even fancy Kevin Kline.

Saturday: a friend phones to moan on about the long hours she works. I am busy sympathising when I remember the healer/warrior advice. Cut her off, mid-moan, and say in my most warrior-like tones that I have to go. Kevin could, after all, be trying to get through.

Sunday: no call.

Monday: I can live once more outside the bounds of prediction. Maybe there's a kind of small print in astrology to say that sceptic's trial periods don't work. But I have emerged crystal-free and Kevin-free - and that's just about all I care about