Phil Cheadle

DCI Jane De Freitas's personal fallout with boss and partner chief superintendent Robert Drake is the least of her worries when three people are shot dead in a petrol station. Nikki and Jack conclude that it is the work of a concealed shooter from long range. A sniper is at large in London. They combine ballistics and wound pathology, along with DCI De Freitas's expertise in victim and killer profiling, to narrow down the suspects. De Freitas contains her undercurrent of animosity towards Drake, as the team work to find the killer apparently striking at random.

The sniper plays a macabre game of cat and mouse with the police, while Jack forms a friendship with the teenage son of one of the victims, offering sympathy and support. Thomas tries to ensure the safety of his daughter Rosie and estranged wife Julia amidst growing public fear, while fighting his urge to interfere in their lives. Nikki and Jack look closer at the targets to elucidate the hidden motive of the killer. The investigation is scaled up by DCI Jane De Freitas, but it's Jack's shocking discovery at one of the victims' homes that leads the team to the perpetrator.