Two hundred meters below the ocean’s surface, you can’t run, you can’t hide, and the truth won’t set you free.

An officer hangs himself in the engine room of naval submarine HMS Tenacity. A woman’s murder bears disturbing similarities to an old case. Lieutenant Danielle “Dan” Lewis grasps for the truth—before it submerges in the gray waters of the English Channel.

Cramped, claustrophobic, and under strict command, the confines of HMS Tenacity are unwelcoming in the best of circumstances. For Dan, the only female aboard, who must methodically interrogate a tight-knit and hostile crew, it’s her own special place in hell.

Recently reassigned to the Special Investigation Branch’s Kill Team, Dan’s hardheaded reputation precedes her. But facing an obstinate ship’s company, a commanding officer too eager to close the case, and a constant threat of unfriendly male interest, she learns that under enough pressure, everyone has their breaking point.