Consider the evidence: in the installation entitled The Bic Art Room, of 1981, in Leiden, inthe Netherlands, Fabre locked himself up in a room for days and proceeded to draw on every available surface - walls, bed, clothes, floor, and his own body - until everything was covered in a cross- hatched biro scrawl. Earlier, in 1978, he had exhibited drawings made with his own blood. In 1991, he covered Tivoli castle in Belgium in biro drawings, wrapping the entire building in paper which was then obsessively blued in Bic and left there for three months, its image mirrored in the castle's lake so perfectly that Fabre was able to exhibit photographs of the building the wrong way up. For next month's Venice Biennale, he will create an enormous globe fabricated entirely from the bodies of beetles, which will represent - as his assistant Tijs Visser says proudly, and with no trace of humour - the largest beetle-construction ever made.
Fabre's visual art is paralleled by performance-works in dance, opera and his own staged texts, in which he has collaborated with composers such as Gorecki and Wim Mertens at venues throughout Europe. Under his direction, dancers imitate the movements of beetles, dressed - when they are not naked - in armour-plated costumes modelled on the carapaces of insects.
For his current showing, as the featured artist of this year's Bath Festival, Fabre has surpassed himself. The series of site-specific installations for Bath, Seven Rooms, is wonderfully inventive, placing his work in new, non-gallery settings of abandoned rooms and odd semi-public places where their strangeness resonates with extraordinary energy.
Accordingly, a specially commissioned essay for the festival by Pavel Buchler meditates on the significance in Fabre's work of the number seven, bringing the seven seals of the apocalypse, the seven dwarfs, the seven samurai, the Magnificent Seven, and everything but the seven kitchen sinks into its orbit. The one thing it doesn't mention is perhaps the only seven- reference of real relevance: the Hollywood film Seven, where the murderer arranges the sites of his kills in a series of carefully wrought, macabre installations. The hanging form of a beetle-encrusted carcass (which recalls Rembrandt and Soutine), the drawing-pinned and bacon-wrapped figure of Me Dreaming and the subterranean-flooded cavern of The Tea-Bags Cellar, where the ceiling is hung with multiple Tetley's, each containing an image of the artist, are all stunningly accomplished examples of mise-en-scene, and so weird and discomforting that they could easily serve as sets from the film. Seven, Fabre has said, "is the number of impossible perfection".
The final, seventh, room of the Bath series forms an appropriately climactic coup de theatre: in the majestic empty space of the disused Walcot chapel, a row of Bic-painted bathtubs covers the floor, looked down upon by the sentinel figures of glass owls mounted high on the walls, their forms blued - naturally - with Bic-ink. The owls, the insects, and the blue of the biro drawings all relate to Fabre's great influence and inspiration, his ancestor Jean Henri Fabre, a late-19th-century entomologist and writer who coined the phrase "the hour blue" to refer to the magical period that occurs when night melts into day. This symbolic interstice is at exactly the point, according to Fabre "when the night animals are going to sleep and the daytime animals are waking up, and there is a moment of sublime stillness in Nature in which everything rips open, breaks apart, changes. That is the moment I have tried to capture."
Born in Antwerp, where he still lives, in 1958, Fabre studied fine art at the city's academy. As a child he created a secret garden which no- one was allowed to enter, and his first experiments in biro-drawings evidently began when he attempted to follow the line of an insect crawling over the page of his sketch-book. His fascination with insects followed the example of his great-grandfather, whose collection he still occasionally plunders, although normally he orders his beetles by catalogue from the Natural History Museum in Brussels or uses the network of insect-collectors in Europe. The German writer (and one-time Nazi controller of Paris) Ernst Junger is a fellow insect-enthusiast and he has agreed to write an essay for one of Fabre's forthcoming exhibitions. Hand-stitching the beetles on to a chicken-wire frame to create his sculptures is, says assistant Tils, terribly dirty work.
In person, Fabre comes across as a bit of an operator. He could, you feel, charm the beetles right out of the trees. With his light-coloured hair brushed back in a quiff, he looks a little like the Hollywood actor Mickey Rourke. Short, fit and wiry, and dressed in a classic artist's mix of the formal and informal - a mac over a smart suit jacket and matching waistcoat worn with blue Levi's and brown suede brogues - he has an actor's intensity and manages to dominate the space around him through sheer force of personality, even it he's just standing there looking bored, as he often is. He keeps carefully to the edge of the press group on a tour of his Bath Festival sites, waiting patiently outside each of the installations, furtively puffing at a cigarette, as if present and absent at the same time. As we shelter from the rain under the canopy of the Holbourne Museum by a window looking into the room housing the modern crafts collection, I ask if he has seen Eric Gill's decorated lawn-roller, which is one of the objects inside. He hasn't, but he knows about Gill. "He used to have sex with his daughters," I say by way of passing the time. Fabre takes a long drag on his fag and exhales. "Sounds Belgian," he says.
The relationship between his visual art and his performance works is, says Fabre when I interview him, an accidental one. "There's only one relationship, and that's me. It comes out of one mind but they are two different mediums," he says. "I think theatre has nothing to do with visual art and visual art has nothing to do with theatre. I learned a lot about space from people like Balanchine but I also learned a lot from the insects, from observing the quality of the way they go through space. The reason I make theatre is because I like to work with people, and there the human beings on stage are the most important factors, while with visual art it's my work that is the most important, and it's a more lonely process. For me, the theatre is like two wooden legs whereas visual art is only one. In theatre you have to step into structures while my visual art is always free of that sort of pressure."
The influence of his great-grandfather is, he feels, overplayed by commentators. "I was lucky in that I had a heritage from when I was younger of photographs, manuscripts and an insect collection in my family, but I was much older when it was given to me. Like any little boy, I took spiders from the earth and pulled out their legs to discover how they worked. I made a lot of drawings and when I was older, about 18, when my mother and father saw them and knew that I was serious they said `Hey, there's a guy in the family who was interested in insects, here's some books about it.' "
Insects, he says, "are like the biggest memory in the world, they are the oldest computer and we're still learning from them. The cybernetic world goes back to insect behaviour to learn how they behave, adapt and metamorphose. It's a very humanistic behaviour but they are almost more complex and more successful than human beings in history, because they have survived and adapted so well." After we have visited the last of the seven sites, Fabre scuttles off to the airport where he will wing back to Belgium to attend a premiere of a new performance that night. Faithful assistant Tijs, who has struggled with the logistical problems of meat, teabags and beetles for weeks now, remains in Bath for the duration.
`Seven Rooms' continues in Bath to 14 June. `The Lime Twig Man' is at the Arnolfini, Bristol (0117 9299191) to 6 July. `Cross in the Silence of the Storm' is at Oriel, Cardiff (01222 399477) to 21 June