Born in 1926, Per Wahlöö was a Swedish writer and journalist who, alongside his own novels, collaborated with his partner, Maj Sjöwall, on the bestselling Martin Beck crime series, credited as inspiration for writers as varied as Agatha Christie, Henning Mankell, and Jonathan Franzen. In 1971 the fourth novel in the series, The Laughing Policeman, won an Edgar Award from the Mystery Writers of America. Per Wahlöö died in 1975.
Joan Tate was born in 1922 of English and Irish extraction. She traveled widely and worked as a teacher, a rehabilitation worker at a center for injured miners, a broadcaster, a reviewer, and a columnist. She was a prolific writer and translator, well known for translating many leading Swedish-language writers, including Astrid Lindgren, Ingmar Bergman, Kerstin Ekman, P. C. Jersild, Sven Lindqvist, and Agneta Pleijel. She died in 2000.