It's Halloween, and the Turtles are staying at April's for the holiday. But when a villain calling himself The King of Thieves steals a golden idol from April's shop and open a portal with it to the spirit world, the Turtles must do everything they can to stop him.

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!! This episode provides examples of

* CatGirl: April's Halloween costume is based on this.
* CryingWolf: The new security system has kept going off accidentally lately. Mikey is thus blindsided when the masked thieves trigger it for real.
* DynamicEntry: Leo stops Donnie from simply knocking on the hotel door, opting instead to kick it open.
* ForHalloweenIAmGoingAsMyself: The reason the Turtles love Halloween: they can walk the streets without having to worry about disguising themselves or keeping to the shadows. They also mentioned that Splinter would take the Turtles trick-or-treating when they were younger.
* HalloweenEpisode
* JerkWithAHeartOfGold:
** Raphael fondly remembers going trick-or-treating with his brothers.
** Leo leans more on the jerk side of it, but he's insistent on recovering the idol. As they were watching her shop, he feels they owe it to April to get back her stolen property.
* NotSoAboveItAll: An incredulous Leonardo wonders why they stopped for caramel apples (which Raph and Mikey are busily eating) on the way to the Blue Star Hotel.
-->'''Raph:''' That one's easy, Leo: 'cause it's Halloween!
* PerpSweating: Catching one of the thieves, Leo wants answers. The guy refuses to talk, until Leo does some fancy swordplay that rips the werewolf mask apart without harming the face. When Leo angrily asks a second time, the panicked thief tells him what was stolen and where their boss is.
* RaceLift: An accidental one occurs midway through when Hadji turns white for a scene. Almost certainly an animation error.
* RecurringExtra: The cops patterned after Eastman and Laird make another appearance. They even get to briefly interact with the Turtles this time, calling them nice kids wearing strange costumes.
* ShoutOut: When the Turtles bump into a couple trick-or-treaters, one is dressed like [[Franchise/ANightmareOnElmStreet Freddy Krueger]].
* SlasherSmile: Leo, who is in a bad emotional and mental place, smiles only once, when he nonverbally asks Don to let him kick down the hotel room door. And it is in this form.
* SnarkBall: Raph and Mikey mockingly suggest every day is Halloween for Casey, but he manages to zing them right back.
-->'''Casey:''' Very funny comin' from a couple of green guys who wear masks every day of the year.
* SparedByTheAdaptation: In the original story, the thug Leonardo interrogated was killed. Here, he doesn't die.
* ThisCannotBe: The King of Thieves after his gremlin servants fade away.
* VillainBall:
** The King of Thieves opts to live up to his title and have the golden idol stolen from April's shop rather than simply buy it. Hadji even points out a wallet that he just lifted on the sidewalk probably has enough money to do that, but the guy refuses. Had he tried PragmaticVillainy instead of hire local thieves for a job, the Turtles wouldn't have found out where he was staying.
** While it's possible the above could be [[JustifiedTrope justified]], as he implies that the statue (an idol to the god of thieves), ''needs'' to be stolen in order to work, nothing could justify him making the gremlins pile the stolen goods in the middle of a busy street while he stands there [[CardCarryingVillain yelling about being the King of Thieves]] in full view of the police.
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