Continuity mistake: Near the end, when the hitman walks out of the diner, the camera focuses on the car in the parking lot, cuts back to the hitman, then cuts back to the car. The problem is the shadows in the first shot of the car are about half a meter long, but a few seconds later they are two meters long. Obviously both takes of the car were taken hours apart.
Audio problem: In the scene where Malcolm is playing Russian Roulette, watch closely around the part when Malcolm begins to stand over the other guy with the gun pointed at his nose. You can hear Malcolm talking, but his lips aren't moving.
Factual error: In the scene where Chaplin and his wife are traveling to Europe by ship (when they find out Hoover has expelled him from the U.S.), the film shows the French Liner "Normandie" as it is leaving New York. The date shown on the film says September 1952. The "Normandie" however, was destroyed by fire in New York Harbor on February 9, 1942 as it was being converted into a U.S. troop ship for World War II. Incidentally, they filmed the scene on the R.M.S. Queen Mary in Long Beach, California, which in reality is probably the ship that the Chaplins actually took to Europe.James Woods
Other mistake: In the scene where Norman, his girlfriend and her family are seeing off her brother at the train station, you can see modern tractor trailers on the interstate highway in the background.