It's 1961, and in a small terraced house in Neasden, overlooking London's busy North Circular Road, 14-year-old Graham Young is hunched over his home-made chemistry set. Obsessed by the mysterious black powder Antimony and a heavy metal called Thallium, Graham knows the only way to become the celebrated toxicologist he boasts himself to be is to test out his chemical theories on a control group. His experiments on family and schoolfriends lead to chronic illness, disfigurement, agonizing death... and to Graham being convicted of murder and imprisoned in a high security mental hospital for the criminally insane. Eight years later, on the recommendation of Dr. Zeigler, famous for his pioneering work with psychopaths, Graham is paroled and sent back into society. But has he really been rehabilitated? His new workmates at the photographic laboratory will soon find out because it's there he's reunited with an old friend he hasn't seen in years--Thallium, bottles and bottles of the seductive stuff....