The action takes place in of September 1943. It opens with one character reading news of Italy's surrender (8 September) and later a radio report of the Battle of Salerno (9-18 September) is heard.
The seaside and pier scenes were filmed in Cromer, Norfolk during a five or six day shoot in September 1978. Parts of the pier were allowed to be dismantled by the film crew for filming as major repairs were due to be undertaken on the pier shortly after. The pier was given an extensive overhaul in 2012 including replacement of parts of the 100 year old structure.
Deborah Watling was actually 30 years old when this was filmed, despite her character supposedly being about ten years younger. Marje Lawrence, who plays her mother, was actually only 16 years older than Watling.
Director Douglas Camfield had previously worked with Deborah Watling (Norma) when he directed her in the Doctor Who serial 'The Web of Fear' eleven years earlier.