Doctor Moon

A shadowy presence in DC's Copper Age, Doctor Moon slipped into the pages of Detective Comics in 1986, courtesy of the celebrated creative team of Mike W. Barr and Alan Davis. With a run touching Suicide Squad and Starman alongside such heavy-hitters as Jason Todd, Catwoman, and Bruce Wayne, this is clearly a character who moves in Gotham's most dangerous circles. Rare in the catalog with only four logged appearances, Doctor Moon is precisely the kind of obscure gem that rewards the dedicated collector willing to dig into the rich, morally complex storytelling that defined the era.