As the Turtles continue resting at Casey's grandma's, tenacious monster hunter Dr. Abigail Finn finds footage of a "green creature" in the woods and will stop at nothing to find it.

Meanwhile, Leonardo has mostly recovered from his injuries, but remains spiritually wounded.

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!!This episode provides examples of:

* AndThatLittleGirlWasMe: Michelangelo's narration in the ColdOpen describes the monster this way.
-->'''Michelangelo:''' It is said that a terrible monster roams these woods. A creature from a forgotten age that brings terror and fear in the dark of night. Yes, there's a terrible monster roaming these woods, "And it's me, booga booga!"
* TheAtoner: Implied to be part of the reason Raph is so kind to Leo in this episode, after Leo's NearDeathExperience made Raph realize he didn't want such an antagonistic relationship with him.
* BaitAndSwitch: April freaking out. Following TheTeaser, you're made to think she's reacting to a monster, but she's just pissed over Casey messing up the floor she just mopped.
* BeleagueredAssistant: Parker assists Dr. Abigail Finn, but behind her back, he calls her a pain in the butt.
* BigNo: April, when Casey shows up messing up the floor with snow on his shoes.
* BrawnHilda: Dr. Finn.
* BreatherEpisode: Taking a break from the main arcs.
* BunnyEarsLawyer: Don describes Finn as a brilliant technologist, gifted biologist and a certifiable lunatic.
* ChekhovsGun: Mike's pistachio nuts eventually help him get close to the Green Man.
-->'''Mike:''' Hey there, you smell these? You want some pistachios? What a smart thing you are. What a smart green man monster. Yeah. Can we keep him?
* TheCuckoolanderWasRight: Finn was right about there being a "monster" in the woods. The point of the heroes' plan is to make her look like a crackpot.
* DeathGlare: April gives this one out to Casey and that scared him enough to get him to leave the house.
* {{Determinator}}: Dr. Finn.
-->'''April''': Maybe this crazy monster hunter person would just give up and go away?
-->'''Donatello''': Dr. Abigail Finn doesn't give up. If she can't find what she's looking for out there, she'll come looking in here. She's obsessed with monster hunting.
* DidntSeeThatComing: There being an actual monster living in the woods.
* DoesNotKnowHisOwnStrength: Dr. Finn is bigger than Casey in terms of muscle mass and she accidentally destroys one of her SORTIE drones by excitedly gripping it too hard.
* ForgingScene: Raph helps Leo forge new swords as replacements for the ones the Shredder broke.
* FunnyBackgroundEvent: When April and Casey are arguing in the beginning, Don is taking apart a toaster in the background, in a manner similar to a small child playing with his toys.
* GentleGiant: The green creature.
* HellYesMoment: The reaction to Leo's suggestion that they go back to New York and settle things with the Shredder.
* HeroicBSOD: Leo spends the episode suffering through it.
-->"I don't need to hear how I messed up in New York, okay? I got my shell kicked. I let everyone down. I lost my swords!"
* HesBack: Leo, with the help of Raph.
* HollywoodHealing: Played with. Leo starts out some bandages and his arm in a sling. Over the course of forging some new swords, the bandages disappear.
* InnocuouslyImportantEpisode: The green creatures will later be revealed as [[Recap/TeenageMutantNinjaTurtles2003S3E16TheEntityBelow humans mutated by the Y'lyntians]].
* JerkWithAHeartOfGold: Rather than get on Leo's case, Raph helps him work through his recent defeat and get back to his old self.
* MissionControl: Parker is this for Dr. Finn.
* MoodWhiplash: Cuts between emotional moments of Leo and Raph forging new swords for Leo, and Donnie and Mikey running around in the woods dressed like Sasquatch.
* MythologyGag: Unlike the comics, where Raph got into a fistfight with Leo and defeated him and then went back to New York alone, Leo announces that is time to Return to New York, like he did in the [[Film/TeenageMutantNinjaTurtles1990 1990 film]].
* NiceJobBreakingItHero: Mikey wandering around in public gets the whole mess started.
* NotSoAboveItAll: Master Splinter as usual:
** When April angrily makes Casey leave, Master Splinter laughs quietly.
** When Casey remarks that he finds it hard to believe that both Mike and Don walked straight into a trap, Master Splinter, who knows his sons, says he believes it without missing a beat.
--->'''Casey:''' I can't believe you bozos walked right into a trap.\\
'''Master Splinter:''' [[DeadpanSnarker I believe it.]]
* OhCrap: Casey, when Dr. Finn shows him a footage of Mikey.
* RealAfterAll: The green creature, as the one Dr. Finn had recorded was actually Mikey.
* SamusIsAGirl[=/=]MonsterIsAMommy: The green creature.
* SelfDeprecation: Casey briefly says this to Mike:
-->'''Casey:''' For crying out loud, Mikey, even ''I'' know we're supposed to be keeping a low profile up here!
* ShowWithinAShow: ''The Monster Hunter'', so TitleDrop ensues.
* ShoutOut: Dr Abigail Finn is meant to be an evil Expy of Creator/SteveIrwin with her show "Monster Hunter" being a reference to Series/CrocodileHunter
* YouHaveGotToBeKiddingMe: Neither Don, nor Casey are impressed by Mike's plan of dressing up like the Green Man and scaring Dr. Finn.
-->'''Don:''' Mikey, ''this'' is your plan?\\
'''Casey:''' Yeah, this is crazy!
* YouMonster: Casey pretends to be captured by Dr. Finn and says this.
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