The Rangers become concerned by the extent of the Sanzu River when water from the Sanzu River begins to seep into our world. Meanwhile, Arachnitor resurfaces and uses the water to prevent himself from drying out. At the Shiba House, Antonio works on the Black Box. After he completes it, he rushes to where the other Rangers are. The Rangers battle Arachnitor and Antonio finally makes it there. He informs Jayden and the others that he has finally unlocked the Black Box. Jayden uses this new power to access his Super Mode and defeat Arachnitor. Once Arachnitor grows into a mega monster, they use a new cannon to destroy Arachnitor.
In a subplot Bulk and Spike attempt to record the Rangers battling the Nighloks on film, so that they can learn some of their moves. But in a comical twist, they forget the SD card for the camera.