When they were little girls, Cassandra and Julia played a game in which they entered an alternate world modeled on the landscapes of Arthurian romance. Now, the sisters are grown and have become hostile strangers—until a figure from their past, a man they once both loved and suffered over, reenters their lives. It is the skittish, snake-obsessed Simon who draws Julia and Cassandra into his charismatic orbit … and into menacing proximity to each other, their discarded selves, and the game that neither of them has completely forgotten. What ensues is both shocking and as inevitable as a classical tragedy.