It's winter in New York, and while Donatello is almost done with the turtle mech, the search for Karai and preparing for the Kraang's second invasion weighs on every hero's mind. Meanwhile, Shredder decides to do a second Villain Team-Up with the Kraang in order to get help for Karai and the crush the Hamato clan once and for all. It's going to be 24 hours that will change...everything.
- Alien Invasion: The Kraang pulled a second rather massive one.
- All Your Base Are Belong to Us: After two seasons of hiding with a number of scares, the Turtles' lair is finally found by their enemies and destroyed.
- Bait-and-Switch: When Irma sees the turtles she starts twitching like she's having a nervous breakdown, but then her twitching becomes more erratic...
- Heroic Bystander: The Pizza Delivery Boy saves a little girl from being crushed by a giant Kraang Mech, he also manages to take down the mech by crashing his moped into it.
- The Chessmaster: It's likely the attack on April while she was with Irma was DESIGNED to force April to flee to a safe place.
- Dirty Cop: Two Kraang disguise themselves as cops to get Casey.
- Even Evil Has Loved Ones: The episode opens with Shredder wistfully remembering a rather happy moment of Karai's childhood. Additionally, Shredder knowingly walks into danger when agreeing to aid the Kraang, since they've promised to return Karai to a human being.
- Evil Former Friend: The Reveal variety where it turns out Irma was a Kraang.
- Improvised Weapon: Mikey uses cookware including a bagel slicer on the Kraang and Ice Cream Kitty swings the freezer door open as a makeshift door slam.
- Mood Whiplash: Irma appears to be having an amusing freak-out when she sees the turtles, but then it's revealed she's a robot controlled by a Kraang. Depending on who you ask, it becomes this again when said Kraang is voiced by Gilbert Gottfried.
- Mythology Gag: Irma's true identity as Kraang Sub Prime is reminiscent of the previous cartoon where Shredder is Ch'Rell, i.e. both reveal that a character thought to be human by both the viewers and characters turns out to be an alien.
- Nice Job Breaking It, Hero: April bringing Irma, a "complete stranger" to quote Splinter, to the Turtle's home turns out to be a big one. Though it was to save who she believed was her friend, the ramifications of doing so were very costly for everyone.
- It's possible the attack on April was meant to invoke this, and force an Idiot Ball on her. Irma and April were under attack by overwhelming numbers, and needed to get somewhere safe NOW.
- Plot Hole: Irma turning out to be a Kraang spy contradicts the scene in "Mousers Attack!" where April gets a call from Irma when at the time of that episode, the Kraang still didn't know where April was. Also, April says she's known Irma for a year, but the events in "Mousers Attack!" happened two years ago.
- Revenge Before Reason: Shredder for now ignores the inevitable betrayal from the Kraang in order to obtain their aid finding and killing the Hamato Clan.
- Robotic Reveal: Irma was really Kraang Sub Prime in a robot body.
- Transforming Mecha: Irma turns outs to be this piloted by Kraang Sub Prime.
- Troubled Backstory Flashback: With a happy flashback done by Shredder when he recalls what happens to Karai.
- The Voiceless: Xever is silent throughout this episode and the next.
- Wham Episode: Irma turns out to be a Kraang spy and with the discovery of the Turtle's home, the Kraang's second invasion begins.
