At 90, Sir David Attenborough might be appearing on location in nature documentaries less than he used to, but he is still very much involved in the editing process, writing the scripts for his narration which give the episodes their intimate and wondrous feel.

BBC One posted a behind-the-scenes video of him working on Planet Earth II this week, documenting his role in proceedings.

Sir David starts by reviewing the edited footage (quite charmingly on VHS), moving back and forth through until he is happy that his words sit right with the action.

Once the script and its timing is in place, it actually only takes him about two hours to record the narration for an hour-long episode, he explains, allowing for the odd re-take when there’s a mispronunciation.

We see Sir David enjoying a good rapport with the sound recordists, joking with them as they put together episodes that will be watched by millions.

“[Attenborough’s] voice makes it feel like he’s only talking to you and he has something very important to tell you,” super-composer Hans Zimmer, who does the music for Planet Earth, comments.