It's a Mad Mad Mad Mad World (1963)

Continuity mistake: In the wide-angle shots of the blue Willys (Jeep) wagon, the windshield is a 2-piece version with a vertical divider in the middle. The close-up shots don't have the divider.

Continuity mistake: In the scene where Dick Shawn and all the characters find the box of money under the big W, Shawn has just thrown Jonathan Winters out of the hole so he would have room to work. But in the next five edits, Winters is both in the hole helping Shawn struggle with the box and is also shown standing outside the hole observing himself along with the others.

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.

Trivia: Arnold Stang broke his left forearm just days before his scenes were shot.

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Trivia: The Sid Caesar blowtorch scene was done 85 times before they got it right.

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Trivia: Phil Silvers almost drowned whilst filming the scene when he drives his car into the river because he couldn't swim.

J. Algernon Hawthorne: Jolly nasty accident there. Jolly lucky nobody was hurt.
Mrs. Marcus: Where did you get that funny accent? Are you from Harvard or something?
J. Algernon Hawthorne: Harvard? Rather not. I'm English.
Mrs. Marcus: Sounds so foreign.
J. Algernon Hawthorne: Really?

Lennie Pike: Everybody has to pay taxes! - Even businessmen, that rob and steal and cheat from people everyday, even they have to pay taxes.

Sylvester Marcus: I'm coming. That's what I'm here for. That's why you had me, Mama, to save you.