If a particle can exist in two places at once, can it ever be anything but elusive? Can you really measure trust when a spy, or is it his twin, may be on your team and on the enemy's simultaneously? Playwright Tom Stoppard examines the theme of free will in a deterministic Newtonian world. Can individuals really control their lives in a clockwork universe? Hapgood cleverly mixes a Cold War spy drama and science. Kerner is a Russian defector, now in the employ of the British secret service, working as a double (or triple) agent. He is a physicist, and his specialty is anti-matter physics. His work has possible applications in former US president Ronald Reagan's nutty money-burning pet project, nicknamed "Star Wars."