When a phone with a brutal drowning recorded on it is handed in to MHU headquarters, the pressure is on for Annika and the team to track down the murderer.
The MHU are sent to Edinburgh to investigate the death of a recently released prisoner whose body is pulled out of the Forth River, imprisoned in a dog cage.
When Morgan starts working at a remote Scottish eco-resort, Annika's trip to visit her is interrupted when a local builder employed by the resort turns up dead in a nearby stream.
