Due to the exclusive news scoop April got from the Ninja Turtles beating Shredder so hard they destroyed his armor, April received a massive bonus. She used some of this bonus to buy pizza from Little Italy's best pizzeria, Pizza Italiano, for the Turtles as thanks. As the Turtles finish up their pizza, however, they are whisked away to the Neutrino Kingdom from in front of April and Master Splinter.
April accompanies the Turtles and Splinter to the beach, when the latter swallows the Nanovampire. April is the one who notices Splinter is sick, and as the Turtles battle the Nanovampire (and later Shredder, Bebop, and Rocksteady) inside Splinter, she provides moral support for Kris Mu as she worries about Splinter's condition. She also buys a fresh bag of ice for Splinter. However, as Splinter's condition worsens, April too, begins to fret. The Turtles end up saving the day, thankfully, and all seven of them go back to the beach (Kris Mu included) to celebrate. Splinter decides to get in on the fun and takes off his robe, revealing nothing but a loincloth, and April calls him a pervert and smacks him to the ground.
April plays a crucial role in this chapter, as she records all of the Neutrino scripture displayed by Kris Mu. Then, when she notices that Kris Mu appears to be depressed or sick, she offers to take the Muta-Stone spirit out to an amusement park so that she can experience the modern world. However, it turns out that what is actually happening is that every time the Turtles super mutate, they are sapping health from Kris Mu. Donatello is able to deduce this by replaying April's footage of the scripture and translating it.
April reports on the disappearing stars and plays a broadcast of the captain of the Endeavour allegedly losing his glasses again. She then appears in the Turtle Lair seconds later, causing the Turtles to become confused before she explains that the report was prerecorded. April, the Turtles, Splinter, and Kris Mu discuss the disappearing stars and Kris Mu reveals it's probably the work of Dark Mu. Splinter, April, and the Turtles (correctly) believe the Foot Clan are working with her in tandem.