1.3 Audio commentary with film historian Michael Brooke and author Johnny Mains
1.4 Undercover Killer: Inside 'The Snorkel' (2018, 21 mins): an analysis of the film and its production by Hammer expert Jonathan Rigby, BFI curator Josephine Botting and cultural historian John J Johnston
1.5 Hammer's Women: Betta St John (2018, 11 mins): film historian Kat Ellinger offers an appreciation of the American actress, singer, and dancer
1.6 Original script ending (10 mins): a reconstruction of the final scenes as they appear in Jimmy Sangster's original screenplay
1.7 Peter Allchorne and Hugh Harlow remember 'The Snorkel' (2018, 8 mins): the Hammer production crew regulars recall making the film