Just who was the arms dealer prisoner swapped for US basketball star Brittney Griner? Viktor Bout was a man who built his empire selling arms to anyone who wanted them, and earned a billion in the process.

BBC business editor Simon Jack and journalist Zing Tsjeng piece together a tale from the secretive world of the international arms trade. They follow Bout's story from Tajikistan to Moscow, the UAE, across Africa and into custody in the USA. Then they judge him for his deeds.

The podcast that uncovers how the world's wealthiest people made their money and asks if they are good or bad for the planet investigates a murky story of post-Soviet wealth built on the sale of death and destruction.