Her Fearful Symmetry
Audrey Niffenegger

Niffenegger will always be known for The Time-Traveler's Wife, but I think she should be better known for this gem of a story. Twins, Valentina and Julia, inherit all of their aunt's possessions, including her flat in London, even though they know nothing about their aunt aside from the fact that she was their mother's twin. Valentina and Julia still live with their parent's in America and they will need to cut themselves off completely from their parents. You see, when their aunt drew up her will she added the stipulation that her twin sister, a women she hasn't seen in twenty years, never set foot in her flat.

This story has everything, old graveyards, family secrets, strange neighbors and even a ghost. The ending is one that will stay with you long after you close the covers of this novel.