Giger says that he does not understand the processes which underlie his painting but that he makes use, essentially, of the mediumistic or 'automatic' style adopted by several surrealists - including Max Ernst, Oscar Dominguez and Wofgang Paalen. Giger maintains that he opens the door to his unconscious mind by confronting his blank canvas and suspending conscious thought. Then, as the spontaneous images start to build before his eyes, he adds details and texture with him airbrush. He says he likes the airbrush because of its 'tremendous directness'. "It enables me", he says, "to project my visions directly onto the pictorial surface, freezing them immediately."

There is no doubt that, in terms of his art, Giger is very much a magician - conjuring dramatic visionary compositions which take us straight into the darker recesses of human consciousness. His work has been praised by the distinguished surrealists Ernst Fuchs and Salvador Dali, and he has been called a genius by psychedelic researchers Timothy Leary and Stanislav Grof. And his work, unquestionably has an authentic magical calibre rarely seen in modern art, which links him in spirit with such tortured masters of the visionary as Hieronymus Bosch and Lucas Cranach.

Image by Giger

Giger lives an unobtrusive existence in a double-storey terrace house just a few minutes drive from Zurich's busy international airport. His living room downstairs is dominated by the remarkable paintings which first earned him international recognition, and which feature Mudusa-like women with ghostly-pale skin, snakes in their hair and strange shapes and forms writhing around them. Claws, needles, machine-guns and barbs also feature strongly in his compositions and his works, for most people, are distinctly disturbing - and fascinating at the same time.

They also have an extraordinary three-dimensional quality which lifts them beyond the plane of the wall so that they become part of the living ambience of the room.

In the center of the long table which occupies this room is an engraved pentagram, and also surreal candlesticks whose flames case an eerie light on the paintings nearby. A tall row of shelves in one corner of the room reveals a row of skulls and authentic shrunken heads from a cannibal tribe. It is here that Giger has placed his Oscar, won for Alien - a tribute to his bizarre imagination.

Upstairs Giger has his studio. At one end it is total chaos - a litter of splattered paint, brushes and discarded works of art. Here he experiments with his airbrush techniques, spraying patterns through metal grids and exploring different textures of light and shade.

At the other end of the long, open room, is a large black table with bulbous legs and an extraordinary mirror sheen on its pristine surface. Fashioned substantially from heavy moulded plastic, it is accompanied by several tall chairs surmounted with skulls and shaped to give the impression of distorted vertebrae. An ashen-grey version of these chairs - seemingly fashioned from bone itself - has pride of place at the head of the table. And gracing the long wall above, is another large panel - this time depicting a horned devil, a silver pentagram and dark, hostile serpents.

Giger has little real explanation for these remarkable manifestations. "I try to come close to my imagination" he says in his broken English, "I have something in my head and I try to work it out - like a kind of exorcism..." Giger recognizes the adverse effect his work has on many of the people who see it - including his respectable and conservative mother - but he is keen to point out that if his work seems dark, he is not this way himself. "My childhood was very happy" he says almost apologetically, "and my parents have been very nice to me". He ponders a while and then adds: "I think most of the images in my paintings are evil, but you can't say that I'm evil. It's just that evil is much, much more interesting than paradise...".

Giger was born in 1940 in the small Swiss town of Chur, an "unbearable" place of "high mountains... and pretty bourgeois attitudes". Growing up there, he had nightmares in his parents house and would imagine "gigantic bottomless shafts bathing in a pale yellow light". In his Necronomicon he writes that "On the walls, steep and treacherous wooden stairways without bannisters led down into the yawning abyss" and the cellar in the house gave rise to the image of "a monstrous labyrinth, where all kinds of dangers lay in wait for me." This feeling is certainly conveyed in his paintings for, time and again, the figures seem trapped and tormented in gruesome, tortuous tunnels and there is no apparent path of escape.

As a child, Giger built skeletons of cardboard, wire and plaster, and he recalls that he also had an "overwhelming disgust of worms and snakes" - a loathing which still manifests in his paintings today. He also had a fascination for pistols and guns of all sorts, and while drafted for military service was nearly shot dead accidentally, on more than one occasion.

If Giger is haunted by images from his past this is quite understandable, for there have been many crises in his life. One of the most traumatic involved the beautiful actress, Li Tobler.

Giger met Li in 1966 when she was eighteen and living with another man. However Giger moved into her attic apartment and in due course they became lovers. Giger recalls that Li "has enormous vitality and a great appetite for life". She also wanted her life to be "short but intense".

Li is the prototype for the many ethereal women in his paintings who peer forth from the torment of snakes, needles and stifling bone prisons - to a world beyond. Giger painted Li's body several times with an airbrush and there are several photographs of her posing naked - like a woman of mystery struggling to emerge from the nightmare that has possessed her soul.

Around this time Giger inherited his present house as a legacy from his uncle, and Li moved in. But the idyll, says Giger, "was all too short". Li had a hectic schedule for her theatrical performances around the country, was irresistibly drawn to numerous other lovers as well, and was beginning to experience the pressures of life in the fast land. On Whit Monday 1975 she shot herself with a revolver.

It may be too simplistic to say that Li haunts Giger still, for his life is full of beautiful and exotic women who are fascinated by his art and by his bohemian lifestyle. But there is no doubting that the simultaneous agony and joy of life with Li Tobler established the dynamic of fear and transcendence which is present in many of his paintings.

Giger maintains that although he has studied occult literature, he is not a magician in the orthodox sense for he does not perform rituals, engage in invocations or summon spirits. But one could hardly find a better temple of the black arts than Giger's main living room, and the beings which inhabit his paintings are themselves like a pantheon of demons. For Giger, in a very real way, makes magic spontaneously. When the thin veil across his psyche is drawn aside just a little, remarkable and tempestuous visions come forth. It is as if the dark gods are emerging once again from the nightmares of his past.