Michael Staniforth, who plays Timothy Claypole, was a talented roller skater and appeared in Starlight Express.
The tapes for the first two series were discovered missing from the BBC archives several years after they were last broadcast. It was assumed they were wiped for reuse by the BBC in the late 1970s. The tapes turned up again in a cupboard at BBC Lime Grove studios when the building was being emptied after the BBC vacated the premises in 1991 prior to it being demolished for housing.
Ann Emery (Ethel Meaker) was the half sister of legendary British TV comedian Dick Emery.
The character name "Timothy Claypole" would later appear in the BBC comedy series "Two Pints of Lager and a Packet of Crisps" originally broadcast between 2001-2011. Clearly a loving reference to the "Rentaghost" character. The later Tim would also be a theatrical comic relief character.
The show's original working title was "Second Chance", reflecting the recently-deceased Fred Mumford's efforts to aid people via the spirit world.