Muscle Men is season one of Extreme, the podcast from BBC Radio 4 that knows no limits. Each action-packed season tells the story of people who’ve pushed themselves to the very edge of what’s physically or mentally possible – and in doing so, have changed the world...

Under the hot California sun, amateur bodybuilders and a former Olympic medallist build the biggest illegal steroid dealing ring the US had ever seen. And America gets ripped.

Episodes will be released on Mondays, starting on Mon 29 July. If you're in the UK, you'll be able to listen to the latest episodes of Extreme - Muscle Men first on BBC Sounds

Extreme: Muscle Men is presented by Natalia Mehlman Petrzela and produced by Novel.