Book excerpt: David Cronenberg is Canada's most provocative director. With internationally acclaimed films such as "Scanners, The Fly, Dead Ringers and "Naked Lunch, he has demonstrated his ability to touch painful nerves and invest his own unique genre with a rare philosophical and emotional intensity. In this stimulating, vivid book--combining memoir, behind-the-scenes movie stories and unsettling and original insights into the traumas of the late 20th century--David Cronenberg reveals the concerns and obsessions which dominate his rich, complex work.