There's a plan to make cold things hot - and hot things cold - using the lost rivers that wind under cities like London. Sounds like magic? Is magic. SCIENCE MAGIC.

Just how do we warm ourselves up in winter without knackering the planet? Or should we just put a few more jumpers on and shiver? And what on Earth have we found in this pub's basement?

We investigate with Alice Bell from 10:10 and Louise Waters from Scene.

Sustainababble is your friendly environment podcast, out weekly. Theme music by the legendary Dicky Moore – @dickymoo. Sustainababble logo by the splendid Arthur Stovell.

Available on iTunes, Acast, Soundcloud & all those types of things, or at sustainababble.fish. Visit us at @thebabblewagon and at Facebook.com/sustainababble. Email us at hello@sustainababble.fish.