DCI Tom Mathias is a man on the run from his past. Having just left the Met police in London, he finds himself holed up in a caravan on the outskirts of Aberystwyth, a university town on the west coast of Wales, sandwiched between the Irish sea and a vast mountainous hinterland. He hardly has time to unpack before being called to the scene of a brutal attack at an isolated chalet in the sand dunes. The victim is believed to be a 64 year old God-fearing woman, Helen Jenkins, but she is nowhere to be found. The investigation leads him to the remote village of Devil's Bridge where for many years Helen Jenkins ran a children's home. The home has long since closed and is now a hotel; eerie, mysterious, atmospheric and a treasure trove of buried secrets. On the nearby bridge railings, Mathias finds traces of blood which leads to his discovery of the missing body in a deep pool at the bottom of the ravine below. Further investigation into the history of the children's home reveals that the attic of the hotel has been left exactly as it was when the home closed down 15 years ago; a snapshot of the tortured past of the children who lived there. The race is on to trace the children who passed through the doors of the home. Only three of the children who lived at the home still live in Aberystwyth and the surrounding area. Hywel Maybury, a troubled loner who works at the local amusement arcade, Jenny James, a rootless wanderer who has only recently returned to town, and Catrin John, who has managed to put the past behind her and leads a quiet suburban life with her husband and newborn baby. Mathias knows that only by unlocking the secrets of what happened at the children's home years ago will he crack the case and reveal the murderer. Secrets which lead to a chase into the hinterland and a climax at an ancient mountain Chapel.

At a remote hinterland farmhouse the body of keen photographer Idris Williams is found following an anonymous call to the police. At first it seems that the reclusive Idris was the victim of a burglary that went horribly wrong, but Mathias's instincts tell him otherwise. Idris's eerie photographs together with the discovery of a battered mouth organ - standard issue by German Wehrmacht during the Second World War - lift the lid on a generation old secret and a love story spanning seventy years. Could Idris's death be linked to a series of murky land deals made by Idris's father which disinherited his neighbour, Eric Roberts, years previously? Can Eric Roberts's only surviving daughter Enid and a letter in her possession explain the mysterious disappearance of three German prisoners of war on Welsh soil in 1944? And if so, what is the connection? Ignoring Chief Superintendent Prosser's orders, Mathias comes into conflict with a local organisation of professional men known as 'The Guild', headed by lawyer Herbert Rees. But when Herbert goes missing the focus falls on his wife Nia. What was the relationship between her and Idris? Did they share more than a love of photography? When Herbert is found to have been kidnapped by an unknown assailant, Nia is forced to confess to a passionate affair with the dead photographer. Mathias discovers Herbert in a garage hideaway, shaken but unharmed and the race is on to find his assailant: the final piece of this epic historical jigsaw.

High in the hills above Aberystwyth, the body of an unidentified young man is found at the bottom of a lake in a disused quarry near the village of Penwyllt. Tommy James whose business is tractors, lorries and trucks is a very prominent member of the close-knit community as are his close friends local publican Dic Rees and garage owner Gwilym Morgan. Naturally wary of strangers, the trio offer Mathias no obvious leads, but when the body is revealed to be ex-teacher and traveller Michael Reynolds whom everyone in the village seems to have had an affection for, tongues start to loosen. Does ex-convict and loner Wyn Bratton hold the key to uncovering the truth? And will Bratton's lonely life in a caravan in the woods and the obvious parallels that it draws to Mathias' own life threaten the detective's ability to decide whether he's the victim or the killer? Who was Dic Rees' wife Lowri having an affair with? Bratton or Reynolds? Did Dic know about it? And what was the link between the two men and Tommy James' 10 year old son Defi? When Gwilym Morgan's apparent suicide in his own garage turns out to be murder and Michael Reynolds is found to have drowned not in the quarry lake but somewhere much closer to home, who can Mathias really trust? In a community that lives by its own rules, what is the price of silence if brother turns against brother and the innocent pay the price? Mathias for one knows the answer.

The body of a young woman is found abandoned but carefully placed in the marshes. The case pushes DCI Mathias to the edge, both personally and professionally.

A mother and her two children fight for their lives following a devastating house fire. As Mathias tries to hunt down the person that started it, he uncovers a controversial plan to flood a remote valley high in the mountains, a plan that spells disaster for the small community that lives there. But is it this plan that led to the fire, or was it something much closer to home?

A young woman goes missing from her flat in a windswept coastal town. Human remains are soon discovered at the address, but they are not those of the missing girl. As Mathias investigates further, he is drawn into a world of hotel workers, on-line lonely hearts and a deadly stalker trapped by the scent of his victim.