Character mistake: When Spencer Tracy is talking to his wife and daughter on two separate telephones, he places the phones up against each other so mom and daughter can talk to each other. One phone should be upside down so it would be speaker to transmitter rather than speaker to speaker.
It's a Mad Mad Mad Mad World (1963)
1 character mistake - chronological order
Directed by: Stanley Kramer
Starring: Spencer Tracy, Peter Falk, Mickey Rooney, Carl Reiner, Jim Backus, Buddy Hackett, Jonathan Winters, Sid Caesar, Milton Berle, Phil Silvers
Continuity mistake: In the last scene when they are all on the fire escape, there is one part where the landing nearly collapses and Sylvester is seen nearly flying off the landing. The next immediate shot shows Sylvester fighting for the ladder. He apparently climbed up the landing and crawled over a bunch of people in a fraction of a second.
Lennie Pike: Everybody has to pay taxes! - Even businessmen, that rob and steal and cheat from people everyday, even they have to pay taxes.
Trivia: Arnold Stang broke his left forearm just days before his scenes were shot.