Karen Pirie is the newly appointed Deputy Inspector of the Cold Case Unite in Fife, Scotland. Her first big investigation takes her 25 years into the past to the national miners' strike. At the time, a kidnapping gone wrong left a small boy missing -- but new evidence discovered by hard-hitting journalist Bel Richmond suggests he might still be alive. As Pirie delves deeper, she realizes the boy's disappearance may be linked to another cold case-- one involving a miner gone AWOL for over two decades.