Factual error: At the end of the episode Sam walks down an alley looking for the son of the murder victim. In the background small split-system air-con units are visible on the outside of some buildings. These were not available at this time. (00:48:30)
Factual error: There is a phone ringing in the police office, but it is using the American style ringing tone - with a single, repeated, long ring - instead of the British ring tone - two short rings repeated. (00:00:24 - 00:01:17)
Factual error: The reflection of a blue DAF XF lorry can be seen in a window. These lorries were not made until many years later. (00:31:51)
Episode #2.3 - S2-E3
Factual error: Sam and Gene arrive at a construction site to investigate stolen explosives. There is a green first generation Range Rover parked on the site. The Range Rover has its driver side (right side) side view mirror mounted on the door. In 1973 Range Rovers had side view mirrors mounted on the front end of the front wing (fender), not the door. The mirror was not mounted to the door until after 1978. (00:08:58)
Episode #2.6 - S2-E6
Factual error: In the back of the record shop amongst the audio equipment you can see 2 A&R Cambridge A60 amplifiers. These were not available until 1977.
Suggested correction: The show is set in a form of purgatory in 2006. It's not really set in 1973.
Factual error: Stopford House in Stockport is used for the exterior shots of the police station. It was constructed in 1975 and wouldn't have existed in 1973 when the show is set.
Character mistake: Sam encounters Marc Bolan in the club and warns him to "drive carefully", aware of Bolan's future death in a 1977 car accident. However, Bolan never learned to drive and he was actually a passenger in the fatal accident. (00:07:55)
Factual error: Gay pride flags are visible in a window. The 6 color flags shown were introduced in 1979 (though an 8 color flag preceded it in 1978). (00:30:44)
Factual error: Throughout the show in many street scenes and visible on some houses are satellite dishes. These were not available in 1973, only terrestrial TV through regular aerials. The first commercial satellite service In the UK was launched in 1989 by SKY.
Factual error: The supposed keys used to kill Colin Clay were a modern type not yet produced at that time.