Although Chesterton is often seen as promoting a superficial optimism in his writing, it would be wrong to presume that he had little or nothing to say regarding the problem of evil. This article examines Chesterton's appropriation of the Free Will Defence (FWD), which is particularly explicit in The Surprise. While Chesterton favoured the FWD, he also recognised the mystery of suffering that is portrayed in the Book of Job. The extent to which evil can be explained is a perennial question that has recently taken the form of a debate between theodicy and defence. The article concludes by looking for a solution in The Man who was Thursday.