The Power Patrol- Mistress Mare-velous, Saddle Rager, the Masked Matter-Horn, Zapp, Radiance, and Fili-Second- have defended the streets of Maretropolis from evildoers for many years now. But now, a vigilante prowls the streets of their fair city at night, bringing with him his own brutal version of justice: the dark, menacing Nighthawk. The Power Patrol vow to bring this vigilante to justice, but how can they hope to defeat a foe who knows all their skills and weakness better than they know them themselves?