In Chris Chibnall's first draft of the episode, the last scene was Tom Miller's (Adam Wilson) deleting files from his computer. They changed it to Alec Hardy's (David Tennant) speech, feeling it would provide a stronger ending and a better cliffhanger.
Deleted scene: Alec Hardy (David Tennant) and Ellie Miller (Olivia Colman) are talking about the investigations near the harbor. Ellie wonders why Alec was so silent during a questioning; Alec tells Ellie he thought she asked good questions.
Deleted scene: Ellie (Olivia Colman) checks in on Tom Miller (Adam Wilson) while he is sleeping. After she leaves, Tom opens his eyes revealing he was only pretending to sleep.
Deleted scene: Ellie (Olivia Colman) arrives home in the middle of the night. Tom (Adam Wilson) is sitting on the stairs. Ellie asks why he still is up, and Tom asks her to tell him what is happening.
David Tennant (Alec Hardy), Jodie Whittaker (Beth Latimer) and Arthur Darvill (Reverend Paul Coates) have all played characters on Doctor Who (2005). Tennant and Whittaker as the Doctor (10th and 13th respectively), while Darvill was Rory Williams, a companion to the Doctor, though it was Matt Smith's (11th Doctor) incarnation he was a companion to.