The spy catchers close in. Klaus Fuchs is caught in the crosshairs. Spymaster Ursula has outwitted the interrogators - but can he? As he settles down in England, British intelligence services are following him at every turn. He is caught in a web of surveillance - and his faith in the Soviets is faltering. How long can he run for? #thebomb

The interrogation of a spymaster. Ursula is questioned as Klaus Fuchs returns to England. Secrets threaten to be spilled and loyalties are tested. The war has ended, and the physicist could have a promising future. But will his past catch up with him? Could British intelligence services be on to him? #thebomb

Lives on the line. The Fuchs family is drawn into the espionage as the atomic bomb project takes a deadly turn. Klaus is at the covert Manhattan Project laboratory in Los Alamos, New Mexico. In this desert terrain, he has lost contact with the Soviets. As the countdown to detonation begins, there's only one person who can be trusted. #thebomb

A double life gets more dangerous. Fuchs joins America's bomb project and the race with Russia is on. But as the nuclear mission ramps up, security tightens too. Now at the heart of the mission, his skills in science and espionage are tested to the limit. #thebomb

The spy meets his spymaster - presenter Rosa Ellis' great-aunt Ursula. She's a housewife and mother living in the English countryside. And she also works for the Soviets. Fuchs and Ursula have a secret list of information that Russia urgently needs to win the nuclear race. Together, they could be the most dangerous spies on the planet. #thebomb

The fate of the world is decided: Klaus Fuchs joins a top-secret atomic mission. The race to build the bomb is on. In Birmingham, England, Klaus Fuchs is working on “TUBE ALLOYS” – the codename for the British atomic bomb project. But at the same time, he’s slipping secrets to the Soviets. Host Rosa Ellis finds out how he did it. #thebomb

The world’s most dangerous spy? A young scientist’s journey into espionage. From a German pacifist family to a Soviet spy ring. Physicist Klaus Fuchs flees Nazi rule for England and joins the race to develop an atomic bomb – whoever gets there first wins the war. Presenter Rosa Ellis discovers how Fuchs’ double life begins. #thebomb

This podcast has been edited for accuracy. Audio was updated on 20th July 2022.

The man who stole the atomic bomb. And why he did it. Klaus Fuchs was a talented scientist - but he was also a Soviet spy. He worked on the British American atomic bomb project, whilst handing nuclear secrets to the Russians. Host Rosa Ellis uncovers the double lives of Klaus Fuchs and her great-aunt Ursula. #thebomb

What does the inside of an atom sound like? Meet our sound designer for Season 2. How Tim Nielsen is using cinematic design. He says he draws inspiration from the human heartbeat. Season 2 begins on 9 July 2022.

"She was not just a spy - she was a spymaster". The family secret of Rosa Ellis, host of season 2 of The Bomb. Emily Strasser takes us behind the scenes of this espionage thriller, as Rosa talks about her great-aunt's double life. Season 2 begins on 9 July 2022.