Three years after a horrific shark attack tore Zoe and Dan apart, the detectives are reunited to solve the murder of a woman who went missing years earlier, while a serial killer is lurking hidden in plain sight.

Zoe and Dan investigate a savage murder with hundreds of potential suspects; Stephen demonstrates that he's willing to go to any length to have Amber.

Zoe and Dan investigate the murder of a predator; Stephen interferes with evidence to prove his abilities as a detective with dire consequences.

A horrific murder puts Zoe and Dan in a race against the clock to stop the killer striking again; Amber attempts to play matchmaker and puts Claire in Stephen's sights.