When the body of a teenage girl is found on a beach, DI Perez leads the investigation. It seems the case may be linked to the disappearance of a young girl 19 years earlier.
DI Perez believes he and his team are finally closing in on the killer as they discover what 17-year-old Catherine Ross was hiding from everyone in the hours before her death.
A journalist is killed in a road accident and it emerges he was an old pal of Perez. As the investigation progresses it seems the victim's return to Shetland was connected to plans for a controversial new gas pipeline.
After a second body is found brutally murdered, DI Perez wonders if the two killings are connected to corporate greed and corruption on the island or to just one woman - Evie Watt.
When a scientist is murdered in a bird sanctuary on Fair Isle and Perez returns to his childhood home to investigate, a storm forces Perez and the suspects to remain enclosed under the same roof.
Time is running out for Perez as prime suspect Peter Latimer lies critically ill in hospital. Was the fire a drunken accident, or was Latimer the second victim of a murderer still free on Fair Isle?