When Clive Hammond was 31, he had a cardiac arrest. His heart stopped for eight minutes. But he can't remember any of it.

What happens when the heart stops - and then what happens next?

Clive sets out to piece together what happened to him. He speaks to his wife Victoria about what went on while he was unconscious, and the impact it had on their lives. He compares notes with fellow cardiac arrest survivor Meg Fozzard about what it's like to have a cardiac arrest as a young person. Former head of first responders at London Ambulance Chris Hartley-Sharpe tells him what goes on in the body during a cardiac arrest, and how they can affect medical professionals afterwards. And he hears the incredible story of Steve Morris, who started carrying a defibrillator in his car after having a cardiac arrest - and then used it to help save someone else's life.

Presenter: Clive Hammond
Producer: Lucy Burns
Editor: Clare Fordham
Technical production: Richard Hannaford