Hyperion
Canterbury Tales in deep space, saturated with Keats, and anchored by the Shrike, one of SF's most terrifying villains. Simmons combined literary ambition with space-opera scale in a way no one has quite replicated since 1989.
It ends with the pilgrims simply arriving, essentially nothing resolved, one reader likening it to “dropping Luke into the trench and never letting us know what happens next.” Many call it “act 1 in a two-act play” and resent that an ending requires buying the sequel. The story-within-a-story shape prevents attachment, jumping narrator and genre just as you invest, and one reviewer dismisses the literary layer as “Keats Mary Sue fanfic.” The sole significant woman’s arc reduces to her pregnancy, “the only female character is basically there to be pregnant.” And the opening hundred-plus pages of unexplained vocabulary are a slog before it finds its rhythm.
The case for it and the rest of the canon open with Pro.
