Magpie by Elizabeth Day (Signed)
Sometimes Marisa gets the fanciful notion that Kate has visited the house before. She makes herself at home without any self-consciousness.
She puts her toothbrush right there in the master bathroom, on the shelf next to theirs. In Jake, Marisa has found everything she's ever wanted. Then their new lodger Kate arrives.
Something about Kate isn't right. Is it the way she looks at Marisa's boyfriend? Sits too close on the sofa? Constantly asks about the baby they are trying for? Or is it all just in Marisa's head? After all, that's what her Jake keeps telling her. And she trusts him - doesn't she? But Marisa knows something is wrong.
That the woman sleeping in their house will stop at nothing to get what she wants. Marisa just doesn't know why. How far will she go to find the answer - and how much is she willing to lose?