Keith Richards on writing "Satisfaction" in his sleep

The Rolling Stones' guitarist Keith Richards was cast away by Kirsty Young in 2015.

He recalls the moment he bumped into his primary school friend Mick Jagger at Dartford train station in 1961, years after losing touch with him. They bonded over a shared love of American blues, which came to define their own sound. Keith Richards laid down the guitar riff for one of the biggest hits, "Satisfaction", on a tape machine in his sleep.

You can listen to the full episode on BBC Sounds.