Sisters September and July share an intense bond, speaking in a secret language and keeping the outside world at a distance. After September is suspended from school, their mother brings them to a remote house on the Irish coast—where July begins to resist her sister’s increasingly sadistic control.
Retired archaeologist Judith Potts lives alone in a faded mansion in the peaceful town of Marlow, filling her time by setting crosswords for the local paper. During one of her regular wild swims in the Thames, Judith hears a gunshot coming from a neighbour's garden and believes a brutal murder has taken place.
