When FBI profiler Kaely Quinn's mother is diagnosed with cancer, Kaely takes time off work to go to Dark Water, Nebraska, to help her brother care for their mother. Upon her arrival, she learns of a series of fires in the small town, attributed by the fire chief to misuse of space heaters in the frigid winter. But Kaely is skeptical, and a search for a pattern in the locations of the fires bolsters her suspicions.

After yet another blaze devastates a local family, Kaely is certain a serial arsonist is on the loose. Calling upon her partner from St. Louis, Noah Hunter, and her brother's firefighter neighbor who backs Kaely's suspicions, Kaely and her team begin an investigation that swiftly leads them down a twisted path. When the truth is finally revealed, Kaely finds herself confronting a madman who is determined his last heinous act will be her death.