Watch Planet Earth S01E04 live on the web
David Attenborough looks at the world's caves, including the Lechuguilla Cave in America, which contains chambers filled with 6m-long crystals.
He observes creatures in Texas and Thailand that never see daylight, and inside Deer Cave in Borneo he finds five million bats whose droppings support an entire ecosystem.
Cast team for Planet Earth S01E04.
No cast for Planet Earth S01E04.
Broadcasts and Catch Up TV for Planet Earth S01E04.
No replays for Planet Earth S01E04 in the next 7 days.
Previous broadcasts on TV
Broadcasts in 2019
17/06/2019 at 15:00
19/04/2019 at 23:00
19/04/2019 at 15:00
19/04/2019 at 10:00
28/03/2019 at 14:00
12/01/2019 at 18:00
12/01/2019 at 15:00
Broadcasts in 2018
27/12/2018 at 18:00
27/12/2018 at 13:00
11/11/2018 at 19:00