C. S. Lewis and J. R. R. Tolkien are two key figures in the Modern Alliterative Revival, and each sought to revive Old English poetics with close to absolute metrical fidelity. While scholarship on Tolkien’s alliterative verse has seen an uptick in recent years, though, Lewis remains the odd poet out. Nominally, this article attempts to assign a composition date for Lewis’s poem “Sweet Desire.” My dating to early 1929 or 1930 associates this text with Lewis’s famous conversion from atheism to theism. More broadly, though, this article tracks one revivalist’s painstaking adaptation of the alliterative meter into Modern English, outlining the technical challenges Lewis had to overcome and which other contemporary revivalists must face as well.