This integrated compendium summarizes the principal characters, events, causal relations and themes of the narrative set in the Wye valley, from the opening river episodes through the investigative unravelling and final restoration.

Setting and principal actors
The action centres on rural Herefordshire along the River Wye (Llangorren Court and Glyngog/Cuckoo’s Glen) and briefly extends to Boulogne. Key figures are Gwendoline “Gwen” Wynn, heiress of Llangorren; Eleanor Lees and household retainer Joseph Preece; Captain Vivian Ryecroft, Gwen’s suitor and investigator; George Shenstone, rival suitor; Jack Wingate, a waterman, and his beloved Mary Morgan. Antagonists include Lewin Murdock (of Glyngog), his French wife Olympe Renault, and Father Gregoire Rogier, a Jesuit-like priest. Richard “Coracle” Dempsey (Coracle Dick), an ex-poacher turned gamekeeper, becomes a pivotal witness and instrument.

Core incidents and conspiracy
Early river scenes establish romantic contact and class intersections: Gwen repeatedly meets Ryecroft while rowing in the pleasure-boat Gwendoline; an assault by intoxicated forest men is repelled by Ryecroft and Wingate, consolidating attachment. Social events at Llangorren—archery, a ball—generate tensions: Gwen accepts attention from Shenstone while fostering intimacy with Ryecroft; jealousy and misinterpretation follow. During a quarrel, an engagement ring placed by Ryecroft is thrown down and later found in a pavilion, intensifying suspicion.

A darker plot unfolds: Mary Morgan drowns after crossing a damaged foot-plank; the coroner records accidental death, but Father Rogier—who observed Coracle Dempsey near the plank—conceals this fact and recruits Dempsey to a clandestine river operation. Lewin Murdock, claiming grievance over inheritance, conspires with Olympe and Rogier to remove the heiress; the plan uses staged evidence and substitution. Gwen disappears after the ball; a female corpse later found and declared “found drowned” is recorded as Mary, but investigative anomalies accumulate.

Investigation, revelation and rescue
Ryecroft, aided by Wingate and others, conducts an independent inquiry. Forensic details—abrasions, crushed vegetation, disturbed coffin—indicate deliberate staging. Delirious confessions from Dempsey and discovery of counterfeit coins and burglary tools link the plotters to Mary’s substituted corpse and Gwen’s abduction. Evidence that Mary’s body was conveyed aboard a French vessel leads investigators to Boulogne.

A nocturnal extraction recovers the novice “Sœur Marie,” who proves to be Gwendoline Wynn. Subsequent inquiries and post-mortem evidence expose the conspiracy; Lewin Murdock dies amid the plot’s collapse, and Rogier and Olympe are implicated and removed. Coracle Dempsey’s admissions are instrumental in establishing culpability.

Denouement and themes
Order is largely restored: Gwen and Ryecroft marry and assume Llangorren; other principals attain reconciled outcomes. The narrative emphasises the Wye as locus of romance and hazard, clerical abuse of influence, the manufacture of staged evidence, and the efficacy of close observation and persistent private inquiry in achieving moral and legal reckoning.