Collects Journey Into Mystery (1952) #83-90. The sound of thunder echoed far and wide when Thor entered the Marvel Universe, facing an array of enemies - from the past and the future, from under the earth and beyond the stars, from distant dictatorships and organized crime! But wherever Thor walks or flies, Loki is never far behind, scheming against Earth and Asgard alike! Featuring the first appearances of such mainstay Marvel miscreants as Mister Hyde and the Radioactive Man!