In 1971, a Soviet research ship drifted into a strange brown cloud near Vozrozhdeniya Island in the Aral Sea—what would later be dubbed Plague Island. What followed was a deadly smallpox outbreak that the USSR scrambled to cover up.

This wasn’t just an accident. Aralsk-7, a top-secret Soviet bioweapons lab on the island, was ground zero for the development of weaponized smallpox, plague, anthrax, and more. It was one of the USSR’s most dangerous secrets—hidden from the world, in violation of every international treaty imaginable.

Declassified documents, CIA files, and explosive testimony from Soviet defector Ken Alibek now confirm the unimaginable: the Soviets nearly unleashed global biological catastrophe.

Welcome to Plague Island. The deadliest place you were never supposed to know existed.