The very case that made Brodie leave the Metropolitan Police returns to jeopardize his private inquiry business, his relationship with Mikaela Forsythe, and perhaps even his life.

Ten years earlier, after Brodie refused to divulge the name of his source in a murder case, Chief Inspector Abberline threatened to have charges brought against him for withholding evidence. The case might very well have won Abberline the coveted new title of Commissioner of Police, and when the "source," a woman, suddenly disappeared, Abberline couldn't forgive Brodie.

Now the woman has returned and says the man she could have helped put behind bars is stalking her and she's afraid for her life. Determined to save her, Brodie searches for her stalker, only to become the prime suspect himself when she turns up dead. With Abberline about to have him arrested, Brodie goes into hiding, insisting he can find the real killer.

Can Mikaela trust that Brodie's telling the truth? Why won't he tell her everything he knows? And what does this all mean for their partnership as well as their personal relationship? She's about to find out as she undertakes her own investigation to prove Brodie's innocence. And when the case takes her into the back streets of London, to the private salon of a man who knew the mysterious woman, is she prepared for what she will find?