A woman’s body is discovered having been brutally attacked. Gently is determined to catch the killer and stop him attacking anyone else. Worried that mistakes could have been down to one inspector, he is determined to get to the bottom of another mystery that is happening within the police force.

Inspector Gently is intrigued as to why a woman has tragically committed suicide. There are too many details that don't add up, and he suspects murder. Why did this woman, a GP, want to end her life? Gently's investigation leads him and his team to the discovery of a bigger industrial crime, more murders and more victims. Gently puts his career on the line to uncover who is really to blame.

Following an armed robbery, Gently seeks to find the armed gang and bring them to justice before more innocent people are shot.