The original short story, which was written in 2004, was largely unavailable to the public until 2013 (2014 for the English-language market), meaning most viewers were unfamiliar with the source material when this adaptation was first broadcast in the summer of 2012.
Unlike all other episodes of the series, there's no Swedish adaptation of this story.
Sarah Smart (Anne-Britt Hoglund) & Donald Sumpter (Fredrik Thorson) also worked together on The Secret of Crickley Hall (2012) as Magda Cribben & Gordon Pyke respectively.