Als Atlee Pine sechs Jahre alt ist, dringt ein Mann in ihr Kinderzimmer ein und entführt ihre eineiige Zwillingsschwester Mercy. Mercy taucht nie wieder auf, Atlee bleibt traumatisiert zurück. Knapp dreißig Jahre später ist sie zur einzelgängerischen FBI-Agentin geworden, die sich ein möglichst einsames Büro nahe des Grand Canyon gewählt hat. Eines Tages wird am Boden der Schlucht ein grausam aufgeschlitztes Maultier gefunden. Ein scheinbar harmloser Provinzfall. Doch dann stößt Atlee auf Spuren einer mörderischen Verschwörung, die bis in die obersten politischen Kreise reicht.

Eeny, meeny, miny, moe. Catch a tiger by its toe. It's seared into Atlee Pine's memory: the kidnapper's chilling rhyme as he chose between six-year-old Atlee and her twin sister, Mercy. Mercy was taken. Atlee was spared. She never saw Mercy again. Three decades after that terrifying night, Atlee Pine works for the FBI. She's the lone agent assigned to the Shattered Rock, Arizona resident agency, which is responsible for protecting the Grand Canyon. So when one of the Grand Canyon's mules is found stabbed to death at the bottom of the canyon - and its rider missing - Pine is called in to investigate.

Mickey Gibson, single mother and former detective, leads a hectic life similar to that of many moms: juggling the demands of her two small children with the tasks of her job working remotely for ProEye, a global investigation company that hunts down wealthy tax and credit cheats. When Mickey gets a call from a colleague named Arlene Robinson, she thinks nothing of Arlene’s unusual request for her to go inventory the vacant home of an arms dealer who cheated ProEye’s clients and fled.

Amos Decker's life changed forever - twice. The first time was on the gridiron. A big, towering athlete, he was the only person from his hometown of Burlington ever to go pro. But his career ended before it had a chance to begin. On his very first play, a violent helmet-to-helmet collision knocked him off the field for good and left him with an improbable side effect - he can never forget anything.

Every day without fail, Travis Devine puts on a cheap suit, grabs his faux-leather briefcase, and boards the 6:20 commuter train to Manhattan, where he works as an entry-level analyst at the city’s most prestigious investment firm. In the mornings, he gazes out the train window at the lavish homes of the uberwealthy, dreaming about joining their ranks. In the evenings, he listens to the fiscal news on his phone, already preparing for the next grueling day in the cutthroat realm of finance. Then one morning Devine’s tedious routine is shattered by an anonymous email: She is dead.