The invention of a cheap and easy-to-use antigravity harness revolutionises society. Humanity takes to the skies in its millions, with huge resultant problems for governments and police. Virtually all aircraft are grounded, because of the risk of collision with a stray flyer. Airborne delinquents and criminals are practically impossible to control and can be lethal. Robert Hasson is a good policeman. But a near-fatal airborne confrontation with a psychopath has left him shattered, both physically and mentally. Sent to Canada to recuperate (and to escape the attentions of a local businessman whose son he has put away), Hasson is a broken man, unable to face human company, haunted by nightmares and certain that he will never again put on an anti-gravity harness. But his Canadian host,...