After Galt (Mark Stevens) has the scuffle with Jardine (Kurt Kreuger), Kathleen Stewart remarks to Galt that his jacket is torn at the shoulder. However it was ALREADY torn when the William Bendix character ran him down in the street. She sat directly across from Galt in the diner and couldn't have missed it the first time.
When Kathleen (Lucille Ball) and Brad (Mark Stevens) realize the white suit must have been taken to a cleaner's, Brad asks her "where's the classifieds?" and she points to the dresser whereupon instead of reaching for the newspaper, he grabs the phone book and looks in the Yellow Pages.
Early in film where Kathleen is seen looking out of the back window of the taxi, she is clearly wearing a ring on her left hand. In all other scenes, like when dancing at the nightclub with Bradford, she is not wearing any ring on the left hand. However, throughout the film, she consistently is wearing a ring on her right hand little finger.
When Kathleen Stewart (Lucille Ball) arrives at Galt's apartment and helps him straighten up a bit following Stauffer's attack on both, she places a lighted lamp back on a table. However when Stauffer left the apartment, it was completely dark.
When private investigator Bradford Galt strong-arms Fred Foss to reveal his home phone number, Foss replies, "CHelsea 4-43510." In the Manhattan phone book for 1946, they only had the CHelsea 2 and CHelsea 3 exchanges. This may be an early version of the 555 prefix which is the convention for fictional phone numbers.
A newspaper ad mentions that a Cathcart Gallery exhibition is by Invitation Only, but then why would it be advertised in the paper?
The taxi chase moves through Manhattan in an impossible way: from Wall Street north on Broadway, then north on Centre Street in Foley Square, then south to Battery Park and the old Customs House along State Street, then on State Street alongside Battery Park in the opposite direction (north) without any U-turn, and finally north up First Avenue to 60th Street (about 5-1/2 miles from Battery Park)--but without any dissolves to indicate elapsed time.