Filmed April 1-late April 1947, the last of RKO's four classic Dick Tracy features released from 1945 to 1947, and the only one in which Ralph Byrd takes second billing. He previously starred in the four Dick Tracy serials from Republic Pictures released from 1937 to 1941 and the one feature before this. He would continue playing the character on television, until his untimely death in 1952.
Several of the character initials combined with the last name are a play on words: Dr. L.E. Thal (Dr. Lethal), Professor I.M. Learned (Prof. I'm Learned), and Dr. A. Tomic (Dr. Atomic).
Of the cast, Anne Gwynne was the last to pass away in 2003 at age 84 at the Motion Picture Retirement Home in Woodland Hills, CA. Edward Ashley lived the longest to age 95, passing away in 2000. Ralph Byrd lived the shortest, passing away at age 43 in 1952. Skelton Knaggs also only lived to age 43, but passed away in 1955.
Pat tells Dick Tracy that Gruesome looked just like Boris Karloff... who plays Gruesome.