A nature documentary narrated by David Attenborough and published by BBC broadcasted as part of BBC Wildlife Specials in 2000. A motorised camera with state-of-the-art microphones disguised as a rock covered in leaves. It was invented specifically for this project of infiltrating a pride of lions to record their lives over a period of a couple of years.
Unfortunately the movie Lions: Spy in the Den is not yet available on HBO Max.