Whilst the investigation is followed in forensic detail, the human element is provided by the interaction of the quirky head of the squad, DI Kevin Bryn, with his team.
Bryn is called out to a shooting on a local surfing beach. The victim, a computer specialist, has a gunshot wound on his forehead. It looks like an assassination.
The forensic evidence contradicts the witness statement and a week into the case, Bryn has no clue as to the identity of the killer or even how the killing took place.
The case, as it spreads across the channel into Europe, leads Bryn into the murky underworld of the dark web and his DS into a dangerous liaison.