April O'Neil comes to in a wrecked warehouse. Eager to resume her mission with the Turtles she recalls her training under Master Splinter and runs and climbs her way through a warren of cargo crates, even as the warehouse is ravaged from the outside by something firing laser beams and strong enough to hurl a truck through the wall. She finally makes it outside into the pouring rain, sensing an unseen enemy is following her. She tries to call in the Turtles for back up using her T-phone but only gets Donatello's voice mail. She quickly makes her way towards the lights of responding police cars...but Karai grabs her before she can reach them! Donatello finally responds, but all that's left of April is her phone.
Earlier that day; the other three Turtles daily training session is interrupted by Donnie and April presenting his latest invention: a series of tiny transponders built into one of April's boots to keep track of her movements through the city, which, given her adventures with the boys, means she gets practically everywhere and will allow the Turtles to map bad guy activity all over the island. Leonardo is impressed. Raphael isn't. April is pleased to have a way to keep track of her daily mileage, which Raph admits is pretty cool. Checking the boot's map against a police scanner the gang notice that a wave of robberies have been taking place at labs all across Manhattan, some by the Purple Dragons. Suspicious that a street gang would be interested in high-tech, the Turtles decide to investigate.
Sunset; Tracking the latest heist back to a tattoo parlour the Turtles confront the gang and overhear the location of their next heist from an unconscious gang members walkie talkie. Sneaking through a pizza parlour they confront another squad of Purple Dragons in an alley and head for the rooftops, discovering the Dragons next target is one of the Kraang's TCRI facilities. A fire fight between the Kraang and the Dragons breaks out with the Turtles caught in the middle. As the police arrive one of the gang tries to bolt with a truck full of stolen Krang tech but Leo takes out it's tires with a shuriken. The Turtles chase the fleeing driver into the subway, where, after clearing out other squads, they discover Foot Clan markings on the walls of a disused subway system that the Foot and the Purple Dragons are using to transport stolen goods. Climbing aboard the roof of one of these trains, they're confronted by Karai and several Foot ninja. Before they can take her down the kunoichi unleashes strange glowing green explosives, demolishing the train and leaving the brothers to eat her dust.