The Trap by Melanie Raabe is set, and ready to spring.

I know who killed my sister.
I wrote this novel for him.

Twelve years ago, Linda's sister Anna was murdered. Her killer was never caught, but Linda saw him. Now, all these years on, she's just seen him again. On TV.

He has since become a well-known reporter, and Linda - a famous novelist and infamous recluse - knows no one will believe her if she accuses him, so she does the only thing she can think of: she writes a thriller about a woman who is murdered, her killer never caught. When the book is published, she agrees to give just one media interview. At home. To the one person who knows more about the case than she does.

He knows what happened that night and she wrote a book about it but, when the doorbell rings, neither of them can be sure how the story will end.