Kaeloo doesn't know where she kept her piggy bank, so she can't give Mr. Cat some money he conned her into thinking she owes him. Mr. Cat holds Quack Quack hostage until Kaeloo gives him the money.
"Let's Play Gangster Poker" contains the following tropes:
- Bait-and-Switch: Mr. Cat says he has a surprise for Quack Quack, and leaves some yogurt on the table in front of him. Quack Quack reaches out for the yogurt, and then Mr. Cat whacks him on the head with a baseball bat and yells "Surprise!"
- Body Pocket: Kaeloo turns her "pockets" inside out to prove to Mr. Cat that she really doesn't have money.
- Edgy Backwards Chair-Sitting: Mr. Cat sees his friends playing poker completely wrong and decides to teach them, so he drags a chair to the table and sits on it backwards.
- Exact Words: When Kaeloo tells Mr. Cat that she doesn't have any money, he reminds her that she has a piggy bank, describing it as a "little piggy which rattles when you shake it". Kaeloo gives the piggy bank to Mr. Cat. Mr. Cat opens it and finds out that there really is no money inside... it was rattling because there was a soda can tab inside.
- Foreshadowing: Mr. Cat says that "he and gangster poker go a long way back". It's later revealed that his dad was a gangster.
- Hammerspace Hair: Mr. Cat dresses up as Jules Winnfield for most of the episode and uses a wig which he uses to store stuff.
- Hypocritical Humor: Mr. Cat calls Kaeloo a "she-devil".
- I Have Your Wife: Mr. Cat takes Quack Quack, to whom Kaeloo is a Parental Substitute, as a hostage so she'll pay him money. It turns out that she doesn't have any because of the ongoing economic crisis. Mr. Cat then threatens to shoot Kaeloo if Quack Quack doesn't pay him, which also fails because Quack Quack doesn't have any money. Mr. Cat is subsequently punished by Kaeloo for what he did.
- Insistent Terminology: Each time somebody says that Stumpy lost the deck of cards, he claims that he just "forgot where he put them".
- Klingon Promotion: Discussed. Mr. Cat becomes a gangster and hires Stumpy to work under him. Stumpy tries to formulate a complex plan to kill Mr. Cat so he can become the boss instead, though he never gets the chance to carry it out.
- Perpetual Poverty: Mr. Cat is stunned when he hears that Quack Quack is broke because the amount of yogurt Quack Quack consumes made him assume that Quack Quack was rich.
- Say My Name: When Kaeloo yells "MR. CAT!", Mr. Cat simply responds by yelling "KAELOO!"
- There Are Two Kinds of People in the World: This quote:Stumpy: In this world, there's two kinds of people. Those who have a banana, and those who dig. You dig.
