Conall, now a trainee detective has moved to Letterkenny and under the mentorship of Detective Aoife Cooney faces new cases, loyalties and conflicts.

Meanwhile, a murder investigation brings Conall and Aoife back to Carraignanaul, the hometown he is trying to escape. Conall reconnects with old friend Sergeant Barry Roche, but remains tormented by one question, what really happened to his father Art?