The cast believed the building they were staying at during filming was haunted. At one point Eve Myles went to ask John Barrowman if she could share his room for the night, to find him wearing freshly-ironed Transformers pajamas when he answered the door.
This is the first time we see Owen use his skills from his previous career as a medical doctor.
An unusual episode in the series in that none of it takes place at Torchwood HQ. The idea behind this was to take the Torchwood team out of their comfort zone.
This episode is eerily similar to a theory formulated from what archaeologists discovered in the medieval village of Wharram Percy in North Yorkshire, England. North Yorkshire is located approximately 300 miles north of London and northeast of south Wales where the series mostly takes place.