Karai's Vendetta
Teenage Mutant Ninja Turtles (2012 TV series) episode
Karai's Vendetta title.png
Season Code: 121
Episode: 21
Original airdate April 27, 2013
Written by Russ Carney & Ron Corcillo
Supervising Producer Ant Ward
Producers: MacGregor Middleton
Joshua Sternin
J.R. Ventimilia
Peter Hastings
Ciro Nieli
Directed by Juan Jose Meza-Leon & Sebastian Montes
Voice Direction Andrea Romano
Supervising Director  Ciro Nieli
Episode chronology
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"Enemy of My Enemy" "The Pulverizer Returns!"

Teenage Mutant Ninja Turtles Season 1
September 29, 2012 - August 8, 2013
List of Teenage Mutant Ninja Turtles episodes


  1. Rise of the Turtles, Part 1
  2. Rise of the Turtles, Part 2
  3. Turtle Temper
  4. New Friend, Old Enemy
  5. I Think His Name is Baxter Stockman
  6. Metalhead
  7. Monkey Brains
  8. Never Say Xever
  9. The Gauntlet
  10. Panic in the Sewers
  11. Mousers Attack!
  12. It Came From The Depths
  13. I, Monster
  14. New Girl in Town
  15. The Alien Agenda
  16. The Pulverizer
  17. TCRI
  18. Cockroach Terminator
  19. Baxter's Gambit
  20. Enemy of My Enemy
  21. Karai's Vendetta
  22. The Pulverizer Returns!
  23. Parasitica
  24. Operation: Break Out
  25. Showdown, Part 1
  26. Showdown, Part 2

Season 1Season 2 - Season 3 - Season 4 - Season 5

"Karai's Vendetta" is the twenty-first episode of the 2012 TV series. It first aired on April 27th, 2013.


While the Turtles are infiltrating an undersea Kraang base, the Foot Clan attempts to capture April, forcing her to fend for herself in a battle of wits against Karai.


Major Characters

Minor Characters


In the Foot Headquarters, The Shredder, in his left hand, is holding/torturing a Kraang that he had captured and interrogates it about why they were strictly pursuing/hunting the Turtles when he had encountered the two aliens in the previous episode. At first, the Kraang's speech is not understandable at all, as they only produce senseless squealing when fully out of their exo-suits. When inserted into its exoskeleton (which Karai was able to take in "The Alien Agenda"), however, it completely refuses to speak in any way. When The Shredder threatens it with one of his unsheathed gauntlet blades, it begrudgingly admits that the girl April O'Neil is the very link that is missing from The Kraang's conspiracy, and that the Turtles are the ones that have been harboring - and succeeding in - protecting her. Shredder then orders his adoptive daughter, Karai, to try to find April and capture her. He believes that, with her 'immense, unequaled value', they could possibly use her as a means to lure all five of his adversaries all the way out from their odd place of hiding.

Down in the sewers, everyone is immersed in their training. While April is there practicing some of her moves alongside Splinter, Donnie and Leo are dueling, and Raph and Mikey are doing so as well. Raph attacks Mikey head on, but the latter then moves into a position that allows him to flip Raph over when he attacks. Mikey joyously celebrates for a moment, but then Raph gets up and grabs him from behind, demanding him to give up. Mikey complies, only for Splinter to step into the scene and teach his pupils yet another valuable lesson. He instructs Raph to grab him from behind in Japanese. Raph does so, just like the latter did with Mikey; but instead of surrendering, Splinter promptly licks Raph in the face. Obviously disgusted by this, Raph lets his sensei go and this allows himself to get easily defeated. Splinter then remarks that Raph should take a bath into consideration...

Just when Leo, Mikey and Raph are all watching "Space Heroes", Donnie comes in, talking about the results of a test that he and April just finished. He explains that The Kraang have recently put a small amount of a certain chemical into the New York City's water supply (which he found out because of the Kraang data storage device that he decrypted), which is extremely dangerous. Mikey then accidentally knocks over the container of purified Kraang water that Donnie managed to segregate from a little bit of sewage, and it spills right onto April's arm, but, oddly, it does not have any noticeable effects on her....She quickly shrugs this enigma off, however - and then decides to go up to the surface to get a bite of some real 'human food' for a change and think about an essay that is due. Donnie then tells the others that they can destroy the underwater Kraang base (which they've determined is where the Mutagen is being put into the water) with another invention of his: A cool-looking submarine. However, it runs primarily on kinetic energy, which means that the Turtles have to constantly supply it by pedaling on stationery bikes (until both of the engines are totally charged).

As they begin to approach the Kraang's secret base, they encounter a large creature that Donnie assumes is from Dimension X. They are able to easily outsmart it, however, and successfully break into the base undetected. When Leo says 'We've got bigger fish to fry now', Mikey playfully cracks a joke to as a mere way to try and pass time: "I don't think we're gonna' find a bigger fish than that."

Meanwhile, April unknowingly encounters Karai on the surface when the former has trouble figuring out how to work a brand new type of food machine up there. After helping April out, Karai asks if she can join her; April actually says yes, but she is still very oblivious to this stranger's true identity. The two then enter Murakami's noodle shop. They begin engaging in a relatively serene conversation and the two are actually able to identify some similarities that they have. Eventually, Karai (who, at first, comes up with the alias 'Harmony' to fool April) ends her facade and promptly decides to reveal herself when April is almost baited into trying her order: Turtle soup!! April then tries to leave, but Karai grabs the strap of her purse from behind and pulls her back, telling her that she is coming with her...Thanks to Murakami, however, April manages to make a quick escape. She steals a Pizza delivery guy's motorized bicycle (much to the guy's resentment), but is pursued by Karai on a motorcycle that she quickly finds in the area.

Just as the Turtles prepare to attack a large horde of Kraang, April calls Donnie at a horrible time. She tells him that Karai is after her, which causes him to panic a tremendous amount - However, he tells her to stay calm as much as possible, but to keep some distance between herself and her pursuer...He and his brothers soon defeat all of The Kraang with relative ease, but Don then tries to urge the others to leave so that they can help April. However, Leo and Raph reminds him that they need to destroy the chemical tanks in the base first before they can rush to her aid. So, Donnie manages to rig a Kraang gun to go off in less than 90 seconds, but the creature from earlier breaks into the room from a hole below and attacks the Turtles, complicating matters further. However, Mikey seemingly defeats it and all four Turtles escape just before the base itself erupts in a massive explosion. However, the creature somehow managed to survive, and it begins chasing down the sub, thinking of it is a female of its very own species!!! The gargantuan beast latches on (much to the turtles' horror and disgust), but Leo pulls down a lever that releases some type of depth charges, which, in turn, cause the creature to release them, leaving it emotionally crushed.

Back in the city, Karai is forced to take to the rooftops (due to a moving van that is backing up and impedes her path forward) and starts tracking April from above for a short while, but the latter unintentionally ends up trapping herself in an alley way. April bravely draws her new weapon (that Splinter offered her a couple episodes back) and Karai compliments its utter 'beauty', before quickly disarming April and throwing the tessen aside. April then tries attacking her opponent directly, but Karai manages to dodge every single one of her attacks. Just when April starts running towards Karai once again, Karai delivers a kick that sends April reeling backwards. She then kicks April into the wall of a building, before mercilessly kicking her again and again in both the shoulders & chest.

April falls down, though gathers just enough inner-strength to get herself back up, but she has already become extremely weak. Karai then grabs April, hoists her up on her knee, and punches her hard in the gut. She then knocks April onto the street's sidewalk with yet another fervent kick. While Karai continues attacking, she jealously demands to know what makes April so very important to everyone. April, however, is able to verbally defend herself and provide her own form of questions. Just when Karai has her truly pinned down, April mentions that she lost her mother. For some reason, this causes Karai to hesitate quite a bit (most likely because something similar might have occurred with her) and she then becomes flabbergasted when she realizes that the two of them actually have a commonality of some sort. April then remembers the lesson that Splinter had taught both her and the Turtles earlier. She then gathers up enough strength to grab Karai by the collar, throw her over her own head and down some nearby subway stairs - and April then escapes on one of the motorcycles, saying to herself, "Not bad for a nobody." Karai quickly gets herself back on her feet as well - but then looks upward and bears what appears to be a rather guilt-ridden expression on her face; Yet again, this might suggest more than a thing or two...

Soon, Donnie gets a call from April and tells his brothers that his "sweet princess" is alive, much to his brothers' annoyance. The Turtles and April all meet back up in the sewer lair, where April tells them all about her own dramatic duel with Karai and her first, laudable victory. As expected, all of the Turtles are quite impressed by what she tells them, but Splinter (who does tell her that she used her training well, on the bright side) is also more or less concerned and tells her that, since both the Kraang and the Foot Clan seem to be after April now, the smartest decision would be for April to stay with them in the sewers as much as possible, since it is the only place that she is truly safe. This results in April protesting - and Donnie briefly cheering with joy....At first, she is very upset, due to the fact that she won't be seeing any of her good friends or family members for quite a while (or going to school), but Leo reiterates to her that everything will go back to normal once The Kraang and Shredder have been defeated for good, and have truly exited out of her life (and when her father has been rescued once and for all), which makes April strictly determined to get her old life back.


  • Several clues are given to Karai's origins:
    • In this episode, April reveals she lost her mother. Karai's reaction implies that she has also lost her mother. This could refer to Karai's possible past as Splinter's daughter, where Tang Shen, Splinter's wife and Miwa's mother, was killed in the fire.
    • The name "Harmony" Karai uses to introduce herself to April can be read with the kanji 美和, which reads "Miwa" in English, and translates as "Beautiful Harmony".
  • The sea monster in this episode is strongly based off the legendary "Loch Ness Monster".
  • The scene where Shredder and the captured Kraang having difficulty talking to each other is loosely based on their 80's counterparts.  
  • This is the first time April used her weapon Splinter gave her in "Baxter's Gambit".
  • Donnie introduces a new invention: the Turtle Sub (a submarine powered by stationary bikes). By accident or deliberation, it could be a pun reference to the Turtle, the first submersible vessel ever constructed, invented by David Bushnell in 1776, which was likewise powered by a pedaling drive.
  • Karai's line that her father "is in kitchen utensils" was likely a reference to the 1987 series, where in the first encounter between Shredder and the Turtles, Raphael replied to the Shredder introducing himself by calling him "a kitchen utensil".
  • Karai's "Turtle Soup" line is loosely based off the well known Shredder quote "Tonight, I dine on Turtle Soup." from past Ninja Turtles incarnations.
  • When the Turtle Sub goes into stealth mode, the lighting makes the turtles look like they all have red bandanas, which was their look in the original Mirage Comics.
  • Apparently, April learned Japanese from the turtles.
  • A very adult joke occurs when the sea monster amorously mounts the Turtle Sub as if attempting to mate. As Red Dwarf's David Lister said, "It's either gonna eat us, kill us, or hump us!".
  • When April steals the Pizza delivery boy's bike, she says "I'll bring it back someday!" This is a reference to the first episode of the Pokémon anime, where Ash stole Misty's bike and said these same lines.
  • This is the only episode that Karai is seen in a civilian outfit.


  • As April heads out of the Lab, her left ear is seen to be tucked under her hair and headband.
  • When the Turtles are getting out of the sub towards the end of the episode, Mikey's mask is purple instead of orange.


Leonardo: "OK, we have to be quiet."
Donatello: "Do you have to say that every time? We're ninjas, we know how to be quiet." (His T-Phone rings, loudly)
Michelangelo: "Ooh, that is embarrassing."


Leonardo: "So Donnie, how are we gonna get out there?"
Donatello: "Don't worry guys, I've been working on something that's pretty awesome."

(In the Turtle Sub, Leo, Raph and Mikey panting from pedaling on stationary bikes.)
Raphael: (panting) "This... is not... awesome."
Leonardo: (also panting) "Seriously Donnie? A submarine powered by bicycles?
Raphael: (still panting) You know what would have been more efficient? Swimming!

(Mikey laughs at the comment)

Donatello: Hey pipe down, guys! Kinetic energy is the only way to charge the engines which should be done...right about now.

(Presses a few buttons which causes the jet engines to activate and the others sigh in relief)

Donatello: "We're almost there. Up periscope.'"

(The periscope comes down and it's made from a toilet seat and the 'toilet flushing' sound effect plays while Leo just stares)

Michelangelo: (Mikey knocks down two Kraang-droids) "That's a twofer! Thank you, and thank you-" :(Raphael stabs two Kraang-droids who where about to approach Mikey from behind)
Michelangelo: (turning around) "And thank you."
Raphael: (yelling and poking Mikey on the head) "How many times have I told you: no celebrating until the fight is over?!"
Michelangelo: (also yelling) "How many times have I told you I assumed it was over?" (Mikey pokes Raph and Raph bends Mikey's finger backwards, causing him to scream in pain)
Donatello: "Children! Children! We have to go!"
Leonardo: "Uhm, have you forgotten a little something called "completing the mission"?"
Donatello: "But April's in danger!"
Raphael: "If we leave now, the Kraang will poison everyone in New York, which last time I checked, includes April!"
Leonardo: "Think, Donnie. How can we take this place out?"
Donatello: "Well... uh... the chemical is highly explosive."
Michelangelo: "How do you know that?" 
Donatello: "Partly because it has a hydro-carbon on its outer ring and partly because of that sign."

(A sign that practically says, "Don't shoot any lasers at the chemical tanks because it will explode.")

Donatello: "Come on, April! Come on, April!"
April: (On the phone) "Hey Donnie!"
Donatello: "April! You're OK! Did you guys hear that?! My sweet princess is alive! Did I mute that?" (the others face palm)
April: "Let's agree that you did."
Donatello: "You got it!"


Leonardo: "Donnie, can you make this thing go faster?!"
Donatello: "Of course I can!" (presses the engine button, which causes them to fall off and go off in another direction)
Michelangelo: "Wow, that is fast!"
Donatello: "PEDAL FASTER!!!" (the others start pedaling faster)
Michelangelo: "Feel the burn! (they pedal and pant a lot faster and harder, but the sea monster is gaining) Go, go, go!"

Donatello: (he looks in the behind them and screams and the sea monster hits the sub in the head to make it stop, then the monster grabs onto the sides of the sub while the Turtles gasp) "That's it! It's got us! We're die!" (the sea monster starts making happy whale sounds as the Turtles stare in horror and disgust)
Michelangelo: "Hey, we're not that kind of sub!" (Leo pulls down a lever and explosives get released and it makes the monster and have its feeling hurt as the Turtle Sub swims away)


April: "So, what brings you to New York?"
Karai: "I'm with my dad. He's here trying to close an 'Old deal'."
April: "Oh! What does he do?"
Karai: "He's in kitchen utensils. Knives, mostly."


Kraang: "Kraang is lacking the knowledge to answer the question needed by Kraang."
Shredder: "Do they all speak like this?"


Donatello: "Great, now we can get back to April..." (the sea monster reappears) "Are you kidding me?!"


Michelangelo: "Alright, victory dance!" (8-bit music plays while Mikey gets into a pose)
Leo, Raph and Donnie: (annoyed) "MIKEY!"
Michelangelo: "Or... maybe later."


Michelangelo: "Woo ho hooo! That was fun!" (gets into pose once more.)
Donatello: "Mikey, that victory dance better not last for more then 4 seconds!" (Mikey dances for that amount of time before exiting the room.)


Karai's Vendetta/Transcript