Oliver enlists a mind-altering superhero named Neocortex to help him become more carefree and spontaneous like Kaz. When the brainwashed Oliver is too reckless during a crisis, Kaz is forced to step up and be the responsible one.

Kaz and Oliver are exhausted and stuck working the overnight shift during a lunar eclipse, when it is rumored that the freakiest patients come to the hospital. When Neocortex checks in with an illness that unintentionally traps people in their worst nightmares, Kaz and Oliver desperately try to stay awake and figure out how to save everyone from their nightmares.

Kaz and Oliver suspect that there could be a hospital mole that is working with the Annihilator.