When the Chief finds Carmen herself inside ACME headquarters and initially thinks she is coming back for good:
Carmen: Now you're dreaming. Chief: Well, then, WHOA, STOP! Uh-uh, NONONONONO—the Hindenburg was bad, but THIS IS—Pat, I'll buy avowel and a consonant, N-O—YOU ARE NOT SUPPOSED TO BE HERE, CARMEN! [Carmen pushes a button, and a cursor appears on the Chief's screen] Chief: No, no, you wouldn't do that, get that thing away from me, you wouldn't do that, Car— [Carmen pushes the cursor on the Chief's mouth, locking it in a box, and then moves it into another direction] Carmen: Sorry, Chief, but Zack and Ivy have foiled my plans one time too many.
Zack thanks Ivy for rescuing him from a dicey situation by going on a Hurricane of Puns with an egg-theme.
Zack: I'm a mere shell of the man I was before that horrible egg-sperience. ... Really, if you weren't so egg-stremely punctual, the yolk would have been on me.
And when Carmen steals the Faberge egg and Ivy and Zack have to face her henchmen, Ivy tells Zack to make like their favorite action heroes, which for Ivy means being the Kick Chick and taking down a henchman. Zack imitates the Three Stooges and totally confuses the other henchman long enough for Zack to crawl underneath the guy!
Ivy: The Three Stooges, Zack? The Three Stooges?!
"When It Rains":
"dur-dun-grrr, dur-dun-grrr, Meat Loaf ain't got nuthin on the Chief-loaf...."
Ivy has just revealed to Carmen that she was the titular new "thief" who had beaten her to the loot that Carmen intended to steal. Just then, The Chief pops in, demanding to know why Zack and Ivy used a C5 corridor without consulting him, only to see Carmen and Ivy together, with Ivy dressed as the The Tigress. He suddenly begins to stammer and look utterly confused.
"Birds of a Feather":
Carmen uses pigeons to thwart Zach and Ivy. Ivy's response:
Ivy: Ugh! One of these days you will find out you are not as clever as you think you are, Carmen Sandiego!
Moe Skeeter and Lars Vegas trying to figure out how to steal Leonardo da Vinci's The Last Supper.
Moe Skeeter: Uh, Lars, the painting's on the wall. Lars Vegas: Right, so what do you need? Bolt cutters? Screwdrivers? Moe Skeeter: No, it's on the wall. Lars Vegas: Of course it's on the wall! This is a museum! Moe Skeeter: No, it's a fresco! Lars Vegas:[grabs Moe]It's a museum! Moe Skeeter: No! The painting's a fresco! Lars Vegas:NOOO! The painting's a da Vinci, youwitlessinsect! So how are we gonna take it? Moe Skeeter: We're not! It's a fresco! And that means it's painted on the wall! [Lars takes out a flashlight to examine The Last Supper] I told you it was on the wall. Lars Vegas: Yeah, but who knew it was on the wall?
Chief: Carmen's henchman Jack O'Lantern was spotted in Scotland, part of the Celtic region, stealing—get this, 'cause I don't—a truck filled with turnips!
Zack overhears Ivy and Carmen confronting each other, and dashes to assist his sister, only to see Carmen Sandiego running down the hallway. He jumps her and ties her up, only for "Ivy" to remove her wig and reveal herself to be the real Carmen Sandiego. The Carmen that Zack just nabbed was really Ivy in costume. Made even funnier by the earlier conversation that he overheard.
Carmen: Interesting costume choice, Ivy. Ivy: And did you really think you were getting out of here dressed like that.
Bit of a Fridge Logic for the episode, but Halloween Costumes tend to be either Nightmare Fuel or a fetish. Which did Ivy assume Carmen was using when she chose her Halloween costume?
"Can You Ever Go Home Again?" two-parter:
In Part 1, Zack and Ivy travel to Buenos Aires in Argentina, and the Chief notes the Overly Long Name it was given when it was originally founded:
Chief: Ciudad de la Santisima Trinidad y Puerto de Nuestra Señora la Virgen Maria de Los Buenos Aires. Whoa, the ZIP Code must've been pi.