Superman #173

This November 1964 DC gem features a cover by Curt Swan (inked by George Klein) that puts Clark Kent's secret front and center — quite literally, as he tears open his shirt to reveal the Superman costume beneath, while a stunned Jimmy Olsen reacts nearby. Standing opposite are two of Superman's most dangerous foes, the green-skinned Brainiac and bald-headed Lex Luthor, who appear to have finally uncovered what the Man of Steel has guarded most carefully. With interior work by writer Jerry Siegel and artist/inker George Papp, this issue promises the kind of high-stakes identity drama that made Superman such a compelling read in the Silver Age.