George Bernard Shaw’s five-part play cycle Back to Methuselah (1921) has not been fully appreciated for its utopian criticality, a criticality that offers a profound reframing of longevity and old age. That it is a utopia in dramatic (rather than prose) form, deploys an unusual mix of largely comic genres and styles, pursues eccentric ideas of Creative Evolution, and is exceptionally long and unwieldy in production has led to a mostly limited and perplexed scholarly reception from within both utopian and Shaw studies. Against this context, this article unearths the utopian potential of Back to Methuselah, where aging and longevity serve to make possible the emergence of superior human capacity, which is uniquely able to establish and sustain a better world because of the qualities acquired through extended life. In particular, it argues that taking account of the play as a utopian text—with its radical representation of old age as cumulative value—expands to include age in addition to existing progressive narratives familiar from utopian literature since Thomas More’s Utopia (1516), which fundamentally rethink identities of class, gender, race, and sexuality.