Goofs

The handkerchief in Jerome Cowan's breast pocket changes in shape in each scene.

At the end of the film, Campbell and Vance are driving in a convertible back to New York. Driving at a normal speed in this type of car would create a wind factor that would at least affect the hats they are wearing in some way as well as Vance's hair. But the hats and the hair are perfectly still during the ride; there is no bending or hair blowing in the wind making it quite obvious they are using a rear projection screen.

Campbell goes to the hospital to visit Carr's worker who was found by Campbell and Vance lying bleeding and almost dead at Carr's cottage. He then sees his body being wheeled out by a hospital worker therefore this now a murder case however Sheriff Amber's office does not conduct a murder investigation specifically regarding the worker. In fact, the killing of the worker is practically ignored and basically just considered a dead witness. The worker happened to be an African-American so perhaps that is a telling sign about the attitude of the filmmakers and screenwriter during that time period.

When Campbell and Vance discovered a practically unconscious bleeding worker at Harvey Carr's cottage; Campbell says that they must take him to a hospital. In the next immediate scene, there are newspaper headlines about Carr's dead body found in a rowboat but no mention about the bleeding worker. Also in such a situation after the worker is taken to the hospital, the cops would normally get involved and question Campbell and his assistant as to how they came upon the wounded worker or Campbell's purpose in going to Carr's cottage in the first place. But when Campbell went to visit Sheriff Ambers' office while the sheriff was conducting an investigation; there was no acknowledgment of Campbell being directly involved at all. The film did not explain the story gap in regards to the bleeding worker and Campbell taking him to the hospital.