TV Some silent footage of the First Doctor actor in a script conference with Stanley Holloway, Griffiths Jones and Clifford Evans, though I can't work out which film (the IMDb suggests nothing).
Billy also turns up briefly in this earlier footage of a garden party, shot in a way which makes him look like he's on a see-saw. Or in Mean Streets.
It's the 1947 British Film Festival and here he is with Joyce Howard, his co-star in Appointment With Crime.
He's in here too having a rather intense conversation with Richard Attenborough. They co-starred in The Lost People.