One cold January morning in 1980, on a beach in Kerry, the body of a newborn baby is found in its most sheltered sand dune. Local Garda Mary Shea is first on the scene. Such a case calls for more than small town policing, and the Dublin major crimes team is brought in to take charge.

But there’s a way of doing things in Kerry, one which Mary understands well. And when she is able to get crucial female witnesses to cooperate, lead detective Matt Foley takes her under his wing. This is the biggest case of his career and he needs all the help he can get.

Mary finds more questions than answers and it becomes clear many locals conduct secret lives – but who would do such a thing?