Factual error: Louis Simo gives his son an Etch-A-Sketch while taking him to school, and later when Louis stops by to see his son at his ex-wife's house, his son is playing with the Etch-A-Sketch in his bedroom. Both incidents take place in the summer of 1959. George Reeves died June 16, 1959, hence the investigation. The first Etch-A-Sketch toys were produced on July 12, 1960 and Ohio Art launched the toy in the United States in time for the 1960 holiday season.
Factual error: In the Louvre, Sophie puts the GPS receiver in a bar of soap and tosses it out the window onto a passing truck. Problem is, the bathrooms in that part of the Louvre don't have windows, or bars of soap (they have liquid soap dispensers).
Factual error: When Clouseau heard the footsteps of what he thought to be a lady and what we afterwards knew was the Russian trainer, he described how tall she was using the English system of feet and inches, not the metric system, which is used in France.
Factual error: The house slides down the hill and breaks apart when Chowder pulls it down. It completely breaks apart. The furnace would have been destroyed, but the house rebuilds itself later on.
Factual error: The main character of the movies buys a pistol that is a 1911 Colt, which fires the .45 round. However, when the police show up at the warehouse, and see the shell casings, they mention as belonging to a .38.
Factual error: A cordless nailgun takes about 2 seconds to recharge and cannot fire consecutive nails nearly as fast as depicted.
Factual error: When the crowd is gathered outside of the Armstrong homes, there is an extra wearing a "G-Unit" shirt. The movie was set in 1999, but G-Unit didn't launch their clothing line until 2003.
Factual error: When Josh Hartnett's character pulls up the bathroom tile and find the cash, the bills are labeled "Federal Reserve Notes." Federal Reserve Notes didn't come into use until the 1960s. Back at the time of the Black Dahlia murder, Silver Certificates were in use.
Factual error: Willow drops cartridges on the ground that appear to be .45ACP rounds. These are considerably larger than the 9mm rounds that Edward's Beretta pistol would actually use.
Factual error: In the scene where Captain Vidal's dinner guests arrive in the rainstorm, Vidal's men are using automatic umbrellas which weren't invented until the 1960s. The film is set in 1944. (00:38:20)
Factual error: When Eisenheim is at the Vienna rail station, catching his train after the Crown Prince has died, the overhead electric cables of the modern railway are visible in several shots.
Factual error: Jasper is implied to live somewhere south/southeast of London, however when Theo meets him at the railway station signs can be seen reading "Alresford", the filming location, which is in Hampshire and too far west to be a plausible meeting place.
Factual error: When Angier and Cutter are looking for a new workshop they enter a room, with a fully glassed wall on one side. A very modern white radiator is in the room. (00:35:00)