'Fiendishly addictive' GUARDIANYour best friend isn't who you think she is. You've been friends since university, when you became the people you are today. You don't see each other enough but when you do it's as if you've never been apart. She's one of the family.

Natty and Sean are happily married. But after Natty spends two weeks away on a school trip with her daughter, Sean tells her that he has fallen in love with her best friend, Eve. He's sorry, but their marriage is over. With no other option, Natty embarks on building a new life for herself. And then she receives the note. Eve has done this before. More than once. And with fatal consequences ...