Nuclear Detectives

The mysterious death in London of the Russian dissident Alexander Litvinenko was a story which could have come from the pages of a dramatic spy novel. But it actually happened, and has still not been fully explained.

This two-part series examines the work of scientists - acting as nuclear detectives - seeking to identify and control the spread of radioactive materials.

Part One: Theft and Smuggling

Given that just one nuclear device in the wrong hands would cause untold devastation and loss of life, keeping track of nuclear material is a top priority.

Where do radioactive materials come from? And how do these become available to the "wrong hands"?

This first programme examines theft, smuggling and what happens next.