I obtained lodgings at Number Twenty-Three, in the second-storey back, in January of 1985. The estate agent quoted a price so astronomically immense that I knew him instantly for a blood-descendant of Blackbeard the Pirate, and he committed further crimes against humanity by demanding three months' rent in advance: payable in the form of cash, cheque, or first-born child. I wrote the highwayman a cheque: he pocketed it, and gave me a look which implied he would return the next day with a crowbar to extract the gold in my teeth.

In the next several months I saw no evidence that the building was infested with ghosts or other supernatural claptrap, except that one of my downstairs neighbours--Mrs Buggins, in the ground-floor front--bore a definite resemblance to a banshee. The only other apparitions worth mentioning were three punk-rock musicians with polka-dot mohawks, who called themselves Snoggo and the Wankers, and who rented rooms directly beneath mine shortly after I moved in. At first I was afraid that their musical rehearsals would keep me awake all night; fortunately, it appears that punk-rock musicians never rehearse.

I confess that I derived a certain pleasure from living in the same rooms once occupied by Mark Twain, and my interest in the man and his work--rather keen to begin with--grew steadily stronger. Gradually one corner of my den was given over to Mark Twain artefacts: I obtained several volumes of his novels and a bound collection of his magazine stories and essays. After long negotiation with several antiques dealers and other extortionists, I became the proud owner of three antique photographs of Mark Twain (one of them autographed); a green armchair that had once belonged to Mark Twain, from his country home in Guildford, Surrey; an Edison's Magniscope film of Mark Twain at Stormfield; an empty balsa-wood box, the label of which assured me that it had once contained Mark Twain Brand Nickel Cigars ("Known to Everyone, Liked by All, Genuine Sumatra Wrapper"); a Mark Twain cigarette-card from a packet of Mogul Cigarette Papers ("Let All Your Troubles End in Smoke!"); and a 1906 four-colour broadsheet advertisement recovered from the wall of an ancient Connecticut barn, sporting Mark Twain's scowling visage and advising me that Mr Twain endorsed the firm of Hilliar & Mallory ("Plumbers, Steamfitters and Gas, Dealers in Stoves, Ranges, Furnaces, and Lead Pipe to the Trade"). These items were all lovingly displayed in a corner of my den, to the vast amusement of my house-guests and the vaster depletion of my bank balance. The empty Mark Twain cigar-box I replenished with a fiver's worth of stogies from a tobacconist's shop in the King's Road, and I evicted a colony of blackbeetles from the upholstery of the armchair. I read the Mark Twain books upon occasion, and went on with what passes for my life.

In November of 1985, Halley's Comet returned. At November's beginning a flicker-dim point of light appeared in the evening sky, midway between Aldebaran and the Pleiades. It drew gradually closer to Earth, elbowing its way past intervening constellations in its haste to keep its appointment with the solar system. Each successive night, the flickering grew brighter as the wanderer returned from outer space.

On Earth, a wide range of reactions were aroused by the comet's approach. The astronomers, for the most part--those dedicated tireless individuals who maintain a constant vigil of the stars, in search of new and different reasons to obtain research grants--the astronomers got off their azimuths, squinted into their telescopes, saw Halley's approach, and harrumphed: "What, a rerun? Seen it before. Already know how it ends. What else is on?" They changed channels and left Halley's alone. But the comet kept hurtling Earthwards. Seventy-three new religions sprang into existence in California, India, and East Grinstead: each of them prophesying the end of the world, and all of them soliciting funds so as not to be caught without bus-fare to Heaven on Judgment Day. None of this occupied a great deal of my thoughts, as I was single-mindedly slaving away at my life's work of grinding out manuscripts for magazine articles, short stories, and novels ... all of which I write in order to help editors find a home for their vastly swollen stockpiles of rejection slips. By the end of January, I had papered the walls of two rooms and the foyer with rejection slips, and was preparing for a similar assault on the den.

On the night of 8 February, 1986, Halley's Comet attained its closest position to the Sun. I was not home that evening, having made one of my frequent nocturnal forays to the local pub, the Wicker Man, in order to conduct further research on the effect of alcohol upon the human nervous system. Towards midnight, however, I was on my way home. As I passed Albert Bridge, I received an excellent view of the approaching comet, a few degrees to the east of Capricorn. What an incredible sight, I realised. To think that all Mankind everywhere are pausing just now, in the midst of their warfare and madness and hate, to look up at the sky for one night filled with wonder and awe, to see the comet return, and all Humanity bears witness to the incredible marvels of our boundless and unlimited universe. There must be some way I can make a buck out of this. Maybe if I sell advertising space on the comet? No, too complicated. Comet insurance? Perhaps. Maybe a book deal with...

I was still wading knee-deep in thoughts, then, when I reached Tedworth Square, climbed the stairs to my second-floor flat, and went in. My conscious mind had gone off on bank-holiday elsewhere as my subconscious mind flung its coat in the general direction of the floor, inspected the latest batch of incoming rejection slips ("Dear Sir: We cannot use the stack of paper you sent us. Somebody typed on it."), went into the den, fixed itself a drink, switched on the late-late movie on Anglia TV (Carry On Caligula, starring Bob Monkhouse and Cicely Courtneidge), and deposited itself in a chair. Then and only then, as I succumbed to the pleasant effects of gin and bitters ravaging my bloodstream and the distant sound of my liver whimpering for mercy, I suddenly became aware of the aroma of cigar smoke.

I turned. Sitting there in his own armchair, filching yet another stogie from my cigar-box while the butt-ends of two others smouldered nearby, and helping himself to my personal whisky, sat Mister Mark Twain.

Not the ghost of Mark Twain, I was certain, nor an actor in crepe whiskers and collodion-putty. An actor would have passed up my cigars in favour of a raid on my refrigerator, and ghosts are not commonly known to fancy Scotch whisky. (The form of spirits preferred in the spirit-world, I am told, is Boo-jolais.) No, the man in the armchair was the genuine article, right enough: Mark Twain himself.