The Age of Fury by John Stephens

In Gilded Age New York, a fierce teenage Irish girl joins forces with a notorious gangster to hunt down her sister's killer—from a New York Times bestselling author who’s worked on Gossip Girl, Gilmore Girls, The O.C., and Gotham.

“Reads more like a hurricane than a novel, gaining momentum, page after page. I loved it—even when I was holding my breath.”—Markus Zusak, #1 New York Times bestselling author of The Book Thief

Caitlin is seventeen when she comes to New York to solve her twin sister’s murder. William is hungry for a chance at redemption. Told from both perspectives, their search for justice pulls them from the city’s darkest corners to glittering ballrooms, where a secret can mean death, and love comes at a perilous price.

Caitlin
Mary, my darling twin. I came on the instant of getting your letter. Leaving home in Ireland, crossing the ocean and still arriving too late. Because you're gone. Murdered and left in a dark alley! But I will avenge you, my love. I swear it. Even if I must make a deal with the devil. Or, in this case, the most blood-soaked gangster in New York.

William
There is blood on my hands I cannot wash away. But if finding this girl's killer proves that I am more than the dark thing inside me, more than a monster, then I will. Only I did not forsee Caitlin. Now I have to make a choice. About who I am, who I will be, and who I love.

In this riveting novel of suspense, two unlikely allies must venture into dangerous places—perhaps into each other’s arms—to solve a brutal crime.