Matthew Tucker, a United States District Judge in Houston, Texas, and former Navy SEAL, receives a death threat demanding he grant bail to a defendant in his court charged with sex trafficking. Tucker's life is further upended when Lucy Alvarado, the teenage daughter of his longtime live-in housekeeper, goes missing. Matt's former lover, the provocative and audacious Carmen Reyes, a U.S. District Judge in Laredo, risks her life and livelihood when she joins Matt in a perilous journey through the lawlessness and rampant crime of today's Mexico to attempt to rescue Lucy, herself a victim of sex slave trafficking. Is Lucy's disappearance somehow related to the death threat? Is Lucy, who Matt loves like a daughter, actually his daughter?