The nation's once beloved TV detective John Chapel lives a reclusive life in the Welsh countryside guilt-ridden for letting his career get in the way of his final months with late wife Elin. But when his neighbor is murdered, John is dragged back into the world by detective sergeant Janie Mallowan. Struggling to rise up in the ranks, she teams up with the widower. Despite their opposing instincts, Jamie's interested in procedure and building a watertight case while John's captivated by character and motives this could be the answer to her waning career. As long as her boss doesn't find out.