Liz has become an expert at spying on her neighbors ever since taking time off to write her first novel. One day, Liz receives a piece of mail for a woman named Sabrina by mistake. She quickly becomes obsessed with Sabrina after what she sees when she tries to return the mail.
Shockingly, Sabrina's husband, Gavin, is found dead just a few days later. Liz is convinced that Sabrina had something to do with it. As her obsession continues to grow, Liz will stop at nothing to prove that Sabrina is guilty.
Meanwhile, Sabrina is more concerned with keeping her roster of men running smoothly despite being a suspect in her own husband's murder. As her life begins to unravel, she wonders if she would have been better off with Gavin still around after all.
Although their lives are worlds apart, Liz and Sabrina actually have a lot in common.
Will Liz uncover the truth about Sabrina before it's too late?
Or will her obsession get the best of her?
Either way, they're both about to find out what happens when worlds collide.