It occurred to me afterwards: what happens when Attenborough is no longer around to coax us out from behind the sofa? He is a one-man Extinction Rebellion.
Attenborough - ever humble, ever magisterial - recognises his extraordinary fortune in being able to travel so far and wide, and interact with so many species now all but lost to us.
A powerful, angry film from a man who has witnessed the destruction of Earth’s habitats.
This is an emotional experience.
Environmental catastrophe can be hard to convey in emotional ways. The scale of it can be deadening. Hearing it from Attenborough, however, gives the message stirring intimacy as well as authority.