There are multiple continuity mistakes with the climactic scene on Jones Beach when photographers get pictures of Ruth showing Bob what she looks like in a swimsuit. Some of the photos published in the newspapers are from an angle where no photographer was standing (worse, those photos also show all of the photographers who were present). The first photo seen in a newspaper shows Ruth's robe laying at her feet on the sand even though Ruth never dropped her robe during the live action. Also, the shadows in the photos do not remotely match the shadows of the live action.
The medium shot of Chuck looking at Bob's address book shows Chuck pointing at and very intently studying a page on the left side, but the close-up POV shot shows that the left side is blank. All of the writing is on the right-hand page.
While Bob and Ruth talk on the beach at night, the bathhouse facing the ocean is shown directly behind them, but in subsequent shots, the ocean is shown behind them. They do not move during the sequence, so this is impossible.
At about 0:36:00 the leg model looks at Bob's address book and the close up of the hand holding it has on clear nail polish, but the actress is wearing dark nail polish.
Ronald Reagan's character stated that Judah Benjamin was the vice president of the Confederacy. Benjamin was a cabinet member but not the vice president. The vice president was Alexander Stephens.
In 1949 May 31st fell on Tuesday, not Saturday as shown on the invitation to the Randolph Girl event.
Bob is in a boat and spots Ruth through binoculars. The shots of the boat show that it is rolling in very heavy waves. When the camera switches to show Ruth as seen through the binoculars, the rolling motion completely disappears.
Chuck's note states his body will wash ashore by the East Bath House, but the next scene shows the Jones Beach West Bath House.
When the judge shouts his recognition of Miss Shoemaker in the old film being shown in court, there is no movement of his face and Bob is shown talking without whatever he is saying being heard.
Ruth tells the class that Czechoslovakia is made up of "several interesting racial strains," and then asks "Mr Benerik" if he is "Croat or Slovak." "Croats" are from the former Yugoslavia (Serbo-Croatia). The former Czechoslovakia was comprised of Czechs and Slovaks. Furthermore, "Mr Benerik's" accent is so atrocious that, even if Ruth did not realize it, his classmate Mr Stravitch would realize it in seconds.