The pin Ronnie steals off another man's coat on the bus at the beginning of the film is the Honorable Service Lapel Button. It was awarded to honorably discharged veterans of World War II. It is also nicknamed the "Ruptured Duck".
The $200 check Ronnie receives for one of his stories would be worth about $3,400 in 2023.
Besides Zachary Scott and Bruce Bennett, ''Danger Signal'' was to co-star another Mildred Pierce (1945) castmember, Ann Blyth being originally cast as Anne. However Blyth's injury in a sledding accident - she suffered a broken back - mandated her being replaced by Mona Freeman who - like Blyth - was borrowed by Warner Bros. from Paramount Pictures.
According to financial records at Warner Bros., Danger Signal (1945) was a box-office success, earning $689,000 domestically and $421,000 internationally.
The screenplay for Danger Signal (1945) was adapted from the 1939 novel of the same name by Phyllis Bottome.