Adventure Comics #385

This October 1969 issue of Adventure Comics puts Supergirl in a genuinely unsettling spot: a mysterious red-haired woman in a dark costume bearing a "K" emblem effortlessly hoists a massive rocket overhead, coolly declaring she's not only more powerful than the Maid of Steel — she's her older sister. Curt Swan's pencils and Murphy Anderson's inks give the confrontation real dynamism, with a wide-eyed Supergirl hovering mid-flight as the city skyline looms below, making the cover question — "Can You Solve the Secret of Supergirl's Big Sister?" — hard to resist. Robert Kanigher writes and Kurt Schaffenberger illustrates the interior story, a creative pairing that always delivered sharp, energetic superhero drama.