This lonely piece of land in the South China Sea is shrouded in terrifying legends. Once, madmen from the 'Ship of Fools' landed here, captured it, and turned it into a real hell. And today it bears the name Prison Island, because it houses a special institution – a strictly guarded psychiatric hospital for dangerous mentally ill criminals. Each day here is filled with madness. But this time, something extraordinary happened: the director of the hospital himself went mad, attacked several people, and was then killed in an absolutely impossible way… Something pierced his heart. This occurred in a brightly lit isolation room with soft walls, which was under constant surveillance, where he was placed after a thorough search. His clothing is heavily bloodstained, yet intact around the wound. The cameras recorded the murder, but the murderer is not on them. There is only one specialist in such impossible crimes in China – the outstanding detective-mathematician Chen Jue…
