Simon Reeve crosses Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan in this four-part series, tracing a route from the Russian border in the northwest to the edge of China, then south to Afghanistan and west to the Silk Road cities of Samarkand and Bukhara. In Kazakhstan he walks through a former Soviet biological weapons plant still holding a hundred strains of plague with almost no security, then visits the shrunken Aral Sea, where fishing boats sit stranded on dry seabed and camel farmers have replaced fishermen. Kyrgyzstan hosts both an American and a Russian military base at once, and Reeve meets a member of a banned radical Islamist group before touring one of the world's most radioactive sites. Uzbekistan's secret police tail him openly as he moves through the country, a blunt demonstration of how the regime handles outside scrutiny. The Tajik leg follows an 800-mile border with Afghanistan, a route that carries a large share of the heroin reaching Europe. Reeve treats each stop as evidence, letting the landscape and the people he meets make the political argument.