Michelle Ryan plays an actress filming a movie about zombies on location in Saint Marie. The episode opens with her battling her way through a horde of the undead. Two years earlier, she appeared in the movie Cockneys vs Zombies (2012), in which she portrays someone who has to fight her way through hordes of zombies, this time in London.
Peter Davison and Michelle Ryan who guest starred in the 2nd episode of Series 3 both appear in Doctor Who (1963). Peter Davison played the 5th Doctor in the original series and Michelle Ryan played one-off companion Lady Christina De Souza in the 2009 special Planet of the Dead (2009) opposite Peter Davison's real life son-in-law David Tennant who played the 10th Doctor. Ben Miller appeared in the 8th season's Robot of Sherwood (2014) as The Sheriff of Nottingham opposite Peter Capaldi as the 12th Doctor.
Dwayne says he was the best Angel Gabriel at school. In real life, Don Warrington (Commissioner Patterson) played the Angel Gabriel in the National Theatre's 1985 Mystery Plays.