For many people, curling is the most confusing Olympic sport. Luckily, here's Sir David Attenborough, the famous British maker of nature documentaries, to explain with some voiceover commentary. Sort of.

"In all my years of exploration," he opens, "these are the creatures I find most curious... The aim of this ritual is to land your walnut in the centre of the nest." Hmm. I don't know if that's... exactly correct.

Attenborough was convinced by BBC Radio host Greg James to overdub the Olympic curlers, from the U.S. and Great Britain.