What planet is he on?

It is early in the morning. It is 8am or thereabouts. I am not at my best at this time. Frankly, I am not sure when I'm at my best, but I am fairly certain 8am is not it. I want to be at home, in bed. I want to be warm and quiet with the duvet pulled cosily over my head. I'm not sure I can cope with being in this greasy spoon just off Shaftesbury Avenue in central London. I'm not sure I can cope with Tom Baker who is HUGE and LOUD and has ENORMOUS TEETH and TALKS THUNDERINGLY IN CAPITAL LETTERS and who is giving me a HEADACHE and who wants to go on and on about his SEX DRIVE.

It is early in the morning. It is 8am or thereabouts. I am not at my best at this time. Frankly, I am not sure when I'm at my best, but I am fairly certain 8am is not it. I want to be at home, in bed. I want to be warm and quiet with the duvet pulled cosily over my head. I'm not sure I can cope with being in this greasy spoon just off Shaftesbury Avenue in central London. I'm not sure I can cope with Tom Baker who is HUGE and LOUD and has ENORMOUS TEETH and TALKS THUNDERINGLY IN CAPITAL LETTERS and who is giving me a HEADACHE and who wants to go on and on about his SEX DRIVE.

I don't have anything against sex drives per se. But, at this hour, I tend to prefer a nice cup of tea, milk, no sugar. I would like a nice cup of tea right now. But Tom is deafeningly unstoppable. Tom tried to be a monk once. But his sex drive rather proved the undoing of him.

"Oh, YES. I was very close to Him - GOD'S NUMBER ONE FAN! - but ended up a martyr to my LUST."

"Tea...?"

"Once I was doing National Service, I discovered SEX. I met Regina, a German girl. I fell on top of her accidentally one night in Düsseldorf and that was the end of God and me."

This is going to be immensely tiring work, I can tell. I suppose Tom Baker is rather marvellous in his way. Or would be, if he wasn't so fantastically exhausting. Does he ever stop performing? Does he ever shut up?

"No, never. The most pitiful thing about actors is that they only ever feel really alive when they are performing, when they are fictional. I am entirely fictional. There is nothing authentic about me. I'll do anything to be worshipped and adored. It was marvellous when I was Dr Who [from 1974 to 1982]. EVERYONE ADORED ME! When the little ones were very frightened, they would huddle into their grannies' BOSOMS. And granny's bosom would, I imagine, TINGLE WITH PLEASURE. So when these grannies would, say, see me in Sloane Square, they'd blink and say 'hello, dear' and their BOSOMS WOULD TINGLE. So it wasn't just children who loved me. I also opened up a world of TINGLING BOSOMS among the old..."

"Perhaps..."

"I carry this in my pocket..." He takes out a gold felt-tip. "In case I'm still asked for AUTOGRAPHS... I always sign in gold... the fans seem to like it. Dr Who was a fantastic job. I was famous in 94 countries. I am still famous in Abu Dhabi, although I'm not sure how to turn this to my ADVANTAGE... HA! I know I'm ridiculous, that's why I'm an actor. I see myself as a professional diverter, taking people away from the horrors of the world..."

"Perhaps..."

"I'm never so real as when I'm entirely fictional, and never so insecure as when I have to be real, which is why I'm garrulous and try to amuse."

'Perhaps..."

"I'll invent things if I can't think what to say."

"PERHAPS WHAT YOU CALL THE FICTION IS THE AUTHENTIC YOU. PERHAPS THIS IS JUST WHO YOU ARE!"

Tom looks startled. I think Tom had forgotten I was here. I think he thinks he's the only one who can speak in CAPITAL LETTERS. He says: "That's a marvellously mischievous comment. It may well sum me up. But I'll never know, and neither will you. I think I'd like a cup of tea. Would you?"

"Oh, go on, then..."

He is still, mostly, an actor, yes. These days, though, it is largely radio and voice-overs and the odd TV cameo. Still, he now has another career on the go. A writing career. He published his autobiography a couple of years back, and has now produced his first work of fiction. It is The Boy Who Kicked Pigs, which will be out next week. It was initially commissioned for children. It's about a boy who does a lot of absolutely repellent things to others then gets his face eaten off by rats. ("The rat now set about the lips of the boy... it stripped the top lip back as far as the gums.") It is not exactly Beatrix Potter. On seeing it, Faber & Faber decided it might not be suitable for children after all. It is now being marketed as a "compellingly grotesque" work for adults. Tom just doesn't get it. "I still think of it as a children's story. Some people were very disgusted by it. Were you disgusted?"

"Well... I..."

"Why do people think they know what's best for children? It's the most terrible MISAPPREHENSION!"

I wouldn't say Tom was bonkers, exactly. But his mind does seem to work in spookily dark ways. He lives in Maidstone, Kent (with his third wife, Sue Jerrard, a TV producer, and their eight Burmese cats) in a house that backs on to a graveyard. Aside from ironing and hanging out the washing - "which I do for Sue, who protects me from the things I'm not good at, like bank accounts or having an accountant" - his hobbies include weeding between the graves and inspecting his own tombstone.

"It's a very old, second-hand one I bought for myself. Now, in glorious bold top-billing, it reads: 'Tom Baker, 1934- ' Sometimes I've actually taken a piece of chalk and filled in the second date, but that is a sign of appalling self-pity. Fortunately, when I go back the next day the weather will have washed the chalk off, because I never press too hard."

There seems to be quite a bit of anger about him, too. He seems to hate quite a lot of people. He hates Esther Rantzen. He hates New Labour - "SHINY, SLIPPERY, AWFUL NEW LABOUR." He hates God and the church. "Blessed are the poor? Isn't that the most amazing paradox?"

Anyway, he is much looking forward to the forthcoming book tour. "Bookshops have become the new cheap theatres, haven't they? So when a shagged out old Time Lord like Tom comes to town, quite a few people might turn up, if only to indulge their nostalgia, mightn't they? I don't mind if they buy the book or not, so long as they are affectionate and adoring. If they can't afford the book, I'll buy it for them. This isn't very commercial, I know, but there you are. I just want the adoration. I have always wanted adoration. I even want adoration from dustbin men. I always put the rubbish out at home and take great pride in it. It's double wrapped and fastened with white tape. No matter how miserable the dustmen's lives are, at least they can say: 'Tom Baker's rubbish is pretty stylish'."

Where does this need to be adored come from, Tom? "My mother, of course." He was born in Liverpool in 1934. His childhood was poor, Roman Catholic, not especially pleasant. "I was very religious and was brought up on melodramas and bigotry and the hideous other convictions that pass for religious faith. I liked all the sniffing of incense.

"My father didn't take any part in my life at all, apart from during my conception. He was in the navy and away all the time. My mother was very unhappy with my father. By the time he retired from the sea she didn't know him. They once didn't talk to each other for nine years. It was incredible to live in this utter, hostile silence.

"Still, I can't exaggerate how wonderful it was to be a poor child in Liverpool during the bombing. That was fantastic: bombs falling everywhere; people being blown up; not having to go to school. Sitting in air-raid shelters. It was absolutely great. I remember telling the first woman who had me - you know, Regina - how grateful I was to the Germans for alleviating me from the tedium of my childhood. I was bombed by the Germans, and then SHAGGED by the Germans, and grateful both times!"

Your mother, Mary-Jane? "She was a cleaner. And the worst cook in Europe. Potatoes with gravy browning. Bread puddings like bricks... I used to have to eat the most terrible shit. But I did it because I loved her. And she loved me. I think she loved me more than the other two. [He has a brother and sister.] She used to tell them: 'Tom is different'.

"I looked after her when she was ill. She had an abscess in her breast, and I used to tenderly dress it. There was an awful hole in her breast, and there was a dressing like a tampon that had to be lowered into the hole, and she showed me how to do it when I was eight."

He wanted, he says, to become a "star" for his mother, and thought he'd start by becoming a saint. "For a poor Roman Catholic with no qualifications, becoming a nun or a priest or a monk was the only way." He joined a monastery on Jersey at 15, and stayed until he was 21. By this time, he says, he was so sexually lonely "my muscles used to crack to put my arms around something. A wardrobe would have done".

His mother was upset, yes. "It had meant a lot of status for her." He did his National Service, joining the medical corps, where he discovered acting. "I did impressions of matron and the padre, and realised I could make people laugh. That stirred me on." Sadly, his mother did not live long enough to see him cast as Dr Who.

He was 26 when he married his first wife, Anna Wheatcroft, in 1960. How do you remember your first marriage, Tom? "Oh, darling, with absolute horror. It was such a failure. I knew on my wedding day it was a mistake. I do so admire those people who walk out on their wedding days, don't you?" He had two sons with Anna - Piers and Daniel - then left. "When my children were little, my knees used to shake I loved them so much." How could you leave them, then? "With great difficulty. I was very disturbed at that time. And, in the end, there was such hostility between Anna and me I felt I was better out of the way."

He was never very good about keeping in touch with his boys. "I am always glad to see them, although it isn't very often. You can't love them all the time, can you?" Can't you? I think, sometimes, he uses invention as a kind of self-justification.

Anyway, he's got a voice-over to do in a studio in Soho. I walk him over. He says, in the monastery, there was always a queue to see the priest for confession first thing in the morning. You know, for all the monks who had erotic dreams during the night. "GOODBYE!''

I go home. Where I have 34 cups of tea and 67 Nurofen. I then get into bed and pull the duvet over my head. It is nice in here. I might never come out.