There is a minor rip off of DOUBLE INDEMNITY in the initial and final sequences, when the central character tells his story into a recording device's microphone. It is a tip off to the mediocrity that ensues.
I know precious little about Director Frank McDonald, but it is obvious that THE BIG TIP OFF cannot possibly rate an inspired bleep on his career chart.
The acting, especially by James Millican, Bruce Bennett, and Cathy Downs as Sister Joan of Arc, saves the film from the trashcan. Conte is not bad but there is not a great deal you can do when you are supposed to be a savvy journalist and you do not even know that your best friend is a crime kingpin who has moved from Chicago - long known as the US crime capital of the 1920s and 1930s, so a place that should immediately make an attentive reporter prick his ears - to Conte's home town. Poor Conte does the best he can with a thankless task which becomes painfully clear when you realize that even a nun who teaches children and lives in the seclusion of her convent suspects and knows more about the villain than Conte does.
Constance Smith has lovely eyes and shows off her legs, but her part and her acting are just as thankless.
Shoddy photography and a poor script do not help this little rip off of ideas you see in other films noir of the late 1940s, and early 1950s.