Sarah Vowell
In 2004, Vowell provided the voice of Violet Parr, a shy teenager, in the Pixar animated film "The Incredibles", and returned to her role for the film's sequel, "Incredibles 2", in 2018. Additionally, Vowell has also lent her voice to the character for various related video games and "Disney on Ice" presentations in the years following the film's release. The makers of "The Incredibles" discovered Vowell from episode 81 – "Guns" "This American Life", where she and her father fire a homemade cannon. Pixar made a test animation for Violet using audio from that sequence, which was included on the DVD of "The Incredibles". She also wrote and was featured in a documentary included on the same DVD entitled "Vowellett - An Essay by Sarah Vowell", where she reflects on the differences between being superhero Violet and being an author of history books on the subject of assassinated presidents, and what it means to her nephew Owen. Vowell also played Fernanda, Theacher "Aunt" Deborah and Mary Kelly in "The School Future".
The Abominable Snowmen
The character of Professor Travers is played by Jack Watling, the father of actress Deborah Watling, who plays Victoria. Norman Jones later played Major Baker in "Doctor Who and the Silurians" (1970) and Hieronymous in "The Masque of Mandragora" (1976). Ralpachan is played by David Baron, often said to be the playwright Harold Pinter under a stage name. Pinter has since denied this rumour. David Baron was indeed Pinter's name for the purposes of Equity, the British actors' union, but he had relinquished it by the time this serial was produced.