A dead man's riddles-and secrets-thrust an FBI codebreaker into a deadly cross-country race for justice in a propulsive thriller by the Wall Street Journal bestselling author of The Cipher.

During a recent undercover sting gone bad, hit man Gustavo Toro died in the arms of FBI Special Agent Daniela "Dani" Vega. But Toro had secrets he refused to take to the grave.

In the event of his death, Toro left behind a video that promises to expose a mysterious mastermind who has been operating with impunity for decades. But there's a catch. Dani's team must follow Toro's cryptic clues on a cross-country hunt for justice, and piecing together his past is more twisted than Dani could have imagined.

But as Dani and her team race to gather the evidence, it's clear this powerful adversary will stop at nothing to keep their secrets-including eliminating those who threaten to reveal them.