In Lewis’ transposition of Milton’s Paradise to a distant world where Adam and Eve do not succumb to Satan, the structure of Eden is radically different from the enclosed garden familiar to most readers. In the novel Perelandra (1944), C.S. Lewis represents the Garden of Eden as an open and ‘shifting’ place. The new Garden of Eden, with Adam and Eve unfallen, is a place of indeterminate future, excitement, growth, and change, very unlike the static, safe, enclosed Garden—the hortus conclusus of traditional iconography—from which humanity is not just expelled but also, in some sense, escapes. The innovation is not in the theological underpinnings that Lewis claims to share with Milton but in the literary devices that make evil in Perelandra seem boring, dead-end, and repetitive, while goodness is the clear source of change and excitement.