In the dead man's apartment Lieutenant Stone addresses a crime scene investigator named Sekulovich. The Sekulovich name was Karl Malden's running in-joke.
As Lt. Mike Stone notes in the Epilog, this episode's eccentric title is from the writings of Henry David Thoreau: "Some circumstantial evidence is very strong, as when you find a trout in the milk." (Journal, Nov. 11, 1850).