Jennifer Egan is known for her formal and thematic virtuosity, a constant reinvention that makes each of her novels feel fresh and surprising. “If I've read it or done it before then I'm not interested,” she claims, describing an “aesthetic … guided by curiosity and desire” (Julavitz). But this isn't the whole story; an exacting reader will find familiar threads running through Egan's fiction. Among the most consistent is an interest in siblings (or cousins, in The Keep): how their relationships evolve over time, as they develop horizontal intimacies apart from the world of parents, and how they negotiate various forms of inequality—for instance, how a more typical sibling contends with a beloved other who is ill or disabled. These themes carry over into Egan's most recent novel, Manhattan Beach. Although many reviewers described it as an abrupt departure (Franklin; O'Rourke; Charles), the novel is consistent with Egan's previous work in featuring a disabled sibling and in being concerned with how genre—whether mystery, romance, PowerPoint presentation, or text message—shapes family dynamics. But where earlier projects are marked by unexpected generic combinations, Manhattan Beach hews closely to the contours of two interrelated forms: the historical novel and literary sentimentalism. At the heart of its thick portrait of a particular time and place is a sibling relationship that becomes an occasion for exploring the possibilities and limitations of genre.