Synopsis: There is a Superman-like hero named David Brinkley. Various intelligence agencies refer to him as "Indigo" (the color of his mask) and "der Ubermensch" (Overman). He comes from the planet Cronk and is vulnerable to the substance Cronkite. Brinkley gradually lost his superhuman powers due to the influence of an unknown enemy, and all other superheroes have retired, disappeared, or died. Brinkley's powers gradually return, years later, in the midst of a mid-life crisis, as criminals swarm Manhattan. (Based on the Wikipedia article)