An innocent accused. An infamous hotel.

And a murder everyone wants to hide.

While recovering from a brutal beating, Atticus Riot is arrested for the murder of his ex-agent—the same agent who left Riot for dead. His wife and partner, Isobel Amsel, watches helplessly as he's taken to San Francisco's notorious 'sweat box' for interrogation by an inspector with a grudge.

Desperate to save her husband, Isobel seeks out the one ally they have—only he's in the infamous Hotel Nymphia, neck-deep in a murder investigation with a ghastly corpse and over three hundred suspects. In exchange for the inspector's aid, Isobel agrees to work as a consulting detective on his case.

Now Isobel needs to prove Riot's innocence while tracking down a killer no one wants caught. The diverging trails lead to an old friend, a tangled web of secret lives, and one all-consuming question: where's the line between justice and murder?