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.