There are two actors who played Mickey Spillane's Mike Hammer (and both share a scene together): Robert Bray in My Gun Is Quick (1957), and the most famous, that came out the same year as this movie, Ralph Meeker in Kiss Me Deadly (1955).
Even though Felicia Farr made her debut in this film under the name Randy Farr, she would make her official debut a year later in Jubal (1956) as Felicia Farr, once again co-starring Charles Bronson. In this movie, they do not have any scenes together but do in Jubal. Bronson, like Felicia, had 2yrs earlier made a significant name change also: from Buchinsky/ Buchinski to Bronson in Delmer Daves' Drum Beat (1954).
Broderick Crawford and Lon Chaney Jr. both played Lennie in John Steinbeck's "Of Mice and Men", Crawford on the stage in New York in 1938 and Chaney in Of Mice and Men (1939).
The role of the narrator switches from Chief Ranger Erickson to Special Agent Madden after the nature of the case switches from being under one jurisdiction to the other.