In 1991, Laura Slatkin published The Power of Thetis: Allusion and Interpretation in the Iliad, in which she argued that Homer knowingly situated the storyworld of the Iliad against the backdrop of an older world of mythos by which the events in the Iliad are explained and given traction. Slatkin’s focus was on Achilles’ mother, Thetis: an ostensibly marginal and powerless goddess, Thetis nevertheless drives the plot of the Iliad, being allusively credited with the power to uphold or challenge the rule of Zeus. Now, almost thirty years after Slatkin’s publication, this timely volume re-examines depictions and receptions of this ambiguous goddess, in works ranging from archaic Greek poetry to twenty-first century cinema. Twenty authors build upon Slatkin’s readings to explore Thetis and multiple roles she played in Western literature, art, material culture, religion, and myth. Ever the shapeshifter, Thetis has been and continues to be reconceptualised: supporter or opponent of Zeus’ regime, model bride or unwilling victim of Peleus’ rape, good mother or child-murderess, figure of comedy or monstrous witch. Hers is an enduring power of transformation, resonating within art and literature.