Based on an original idea by bestselling crime writer Val McDermid. From the producers of Happy Valley Series 1 & 2. Passions run high in an explosive return of this critically acclaimed crime series. Lab assistant Emma Hedges is now training to be a forensic chemist, and on the cusp of seeing her mother’s murder case finally resolved. Daniel is to give evidence against his father. Will Emma and Daniel’s relationship withstand the pressure? Will justice be served? Meanwhile, professors Sarah Gordon and Kathy Torrance need all the scientific skill they can muster. Human remains wash up at a loch. Professional and personal allegiances become entangled. Homemade devices are going off around Dundee, with critical clues hidden inside the bombs. Will the team track down the bomber before their identity goes up in smoke? Starring: Molly Windsor, Laura Fraser, Jennifer Spence, Michael Nardone and Martin Compston.