Aiden Fleischer, a bookish priest, finds himself transported to an alien world. With him is Miss Clarissa Stark, a crippled hunchback of exceptional ability, wronged by an aristocrat and cast out from society. On the planet Ptallaya, under two bright yellow suns, they encounter the Yatsill, a race of enthusiastic mimics who shape their society after impressions picked up from Clarissa's mind. Creating a faux London, the alien creatures enroll Clarissa in their Council of Magicians and Aiden in the City Guard. But why does the peaceful city require guards?.