The first film in what was meant to be to be a mystery franchise focused on blind detective Duncan Maclain who solved murders with the help of his seeing eye dog, Friday. When the second entry, L'oeil caché (1945), failed to elicit sufficient interest, MGM ended the series.
Baynard Kendrick was a mystery writer. He wrote about 13 to 14 novels concerning Duncan Maclain. He is also credited with creating the characters on the TV series Longstreet (1971) that chronicled the adventures of a blind detective.
A news item in 1942 noted that Friday, the dog star, was making an extensive personal appearance tour with his trainer, William Steuer, that was designed to focus attention on the government's need for more dogs in war work. Unfortunately, the uncooperative dog, son of silent canine star Flash the Dog, failed to earn any more roles after appearing in the next Duncan Maclain mystery.
Donna Reed had been a working actress about a year in supporting roles but was still three years away from her big break in 1945 with Le Portrait de Dorian Gray (1945) and, most famously, La vie est belle (1946).
Fred Zinnemann had little interest in this film, recalling, "I didn't like it much," "liked the writer, Guy Trosper," "The only pleasures were working with the marvelous Ann Harding and with Donna Reed, who was delicate and charming." Saying further: "the dog was good for only one take, would then get bored, run away and hide..."