Gunn's literary agent was approached in 2011 by a production company looking for Christmas novels to adapt into screenplays. Her agent suggested the novel "Finding Father Christmas". On pitching the story to Hallmark Movies & Mysteries in 2012, it was rejected due its lack of romance. Gunn's agent then made the suggestion to combine the first novel with parts of its sequel, "Engaging Father Christmas", as the latter novel featured a romantic plot for its main character. The two novels were reworked into a combined treatment, which was again pitched to the channel in 2013. It was again rejected, but with the possibility of reconsideration if further adaptations were made, in particular relocating the novel from England to North America. Following further adaptations, Hallmark approved the treatment of the novels in 2015, leading to the development of the screenplay. Gunn went on to publish an ebook ("How My Book Became A Movie:A True Story") in 2016, detailing her experiences of the process, from the origins of the novel to the film's production.