Scriptwriter John Mortimer recalls in his 1994 autobiography, "Murderers and Other Friends", that Sir Laurence Olivier's memory for dialogue had entirely disintegrated (he was in his late 70s), so his lines had to be written on large sheets of paper and hung out of shot.
The Toyah Willcox character Freak is seen reading a book which appears to be "The Ebony Tower" by John Fowles.
The painting that Breasley describes in his last scene with David, over which the end credits scroll, is Paolo Uccello's "Saint George and the Dragon", and as of 2021, it is still held by the National Gallery in London.