Elly Parker helped a perfect stranger. She didn't know he was the perfect killer...in another "unguessable and unputdownable" (Alex Michaelides, #1 New York Times bestselling author) psychological thriller from the author of Witness 8.

One offers a helping hand. The other is your worst nightmare...

Social media influencer, Elly Parker, had the perfect life, that is until she discovered her husband had been having an affair with her best friend.

But as hurt, betrayed, unmoored as Elly is, she has made it her mission to help others in need. Even strangers.

When Elly meets a man on the steps to the subway platform, crutches in one hand and a yellow suitcase by his feet, she can't help but feel sorry for him.

Just as he planned.

This small act of kindness sets off a change of events more terrifying than anything she ever could imagine.

To survive, Elly will need to convince the world what happened to her was real. She needs a lawyer who can bend the rules to find the truth. Eddie Flynn and his team must find the stranger with the yellow suitcase. But little do they know this cunning killer is a master manipulator and is always one step ahead.