Set two generations before the destruction of the legendary planet and the birth of Kal-El (Superman), 'Krypton' follows Seg-El, the legendary superhero's grandfather. In a society fractured by rigid caste divisions, Seg-El lives as a rankless pariah after the House of El was stripped of its honor and cast out of high society following his grandfather Val-El's rebellion against the theocratic ruling council. Seg-El's fate takes an unexpected turn when he is approached by Adam Strange, an enigmatic Earth-born time traveler who warns him that a cosmic entity known as Brainiac is traveling across time to eliminate Kal-El by destroying Krypton ahead of schedule. Faced with a devastating dilemma—save his home planet or let it perish to ensure his future grandson's destiny as Earth's greatest protector—Seg must navigate deadly political intrigues and form tenuous alliances across rival military and political factions in Kandor City. As the threats mount from internal civil rebellion, the militaristic General Dru-Zod arriving from a changed future, and the encroaching terror of Brainiac and Doomsday, Seg-El must fight to redeem his family's honor and preserve the timeline to ensure the survival of hope across the galaxy.