Sam Higgins Sam Higgins arrives at the Welsh village of Tan-Y-Bwlch to take over the North Stack lighthouse, a place the locals insist is haunted. There, he meets Alice Bright, who explains that she belongs to a "psychic society" and wants to tag along to probe the so‑called "legend of the phantom lighthouse." Sam, wary of distractions, declines the request and concentrates on his new post.
Back at the harbor, David Owen, the Harbour Master, fills him in on why the lighthouse is considered cursed: Sam’s predecessor, Jack Davis, vanished without a trace, and the chief keeper before him met a similar fate. There’s also mention of a shipwreck from the previous year, a disaster some locals blame on the phantom light. The eerie history adds weight to Sam’s vigilance as he tries to start fresh in a place already thick with superstition.
A few unsettling interruptions follow. Jim Pearce tries to grease his way into the assignment by bribing Sam to let him reach the lighthouse, and Sam quickly suspects that Jim might be a reporter in disguise. Alice overhears Jim asking about hiring a boat, and she uses her influence to press her case, though her efforts don’t win him over. Later, Owen, Dr. Carey, and others ferry Sam by boat toward the lighthouse. On arrival, the doctor examines Tom Evans, a troubled man among the resident staff. Evans suddenly strains against his bonds and even menaces the doctor, who decides he cannot be moved in his current state. For Sam’s safety, Evans is restrained for the moment, with Claff Owen and Bob Peters at hand to assist.
The night grows stranger when Jim arrives on a boat that is inexplicably out of petrol, bringing with him an unexpected stowaway: Alice. Sam begins to question his guests more sternly, and Alice reveals a more dramatic backstory, claiming she is “an actress hiding from the police” after a knife‑fight between two would‑be suitors. Meanwhile, Jim’s true intentions surface as Sam pieces together his motives, and the danger of saboteurs looms over the isolated beacon.
As the tension mounts, eerie incidents escalate. A fire erupts near Tom’s bed, and Sam hears Jim plotting with Alice while admitting he’s not a mere reporter. The fear of sabotage grows: Alice is sent to fetch Sam, but Tom, who has been untied by Claff, sneaks up and hovers close. When Sam and Alice return, Tom locks them all inside the bunkroom. Undeterred, Jim climbs down the lighthouse and swims to the village to warn the coast guard, while Claff regains his composure and unlocks the door so Sam can begin repairs on the light.
The menace behind the plot becomes clearer as they overhear Dr. Carey talking in hushed tones to Tom. The doctor is revealed to be the mastermind behind the danger to the Mary Fern, and the truth pushes the tension to its peak. With the light sabotaged and a decoy light blazing elsewhere, the crew scrambles to restore the beacon just in time. Jim’s escape attempt is thwarted, and Bob and Claff awaken to help, allowing Sam to work toward restoring the vital signal.
With the lighthouse’s beam gradually realigned, Sam and Dr. Carey confront the mounting suspicion that the doctor engineered the crisis. The Mary Fern is saved at the last moment, but the confrontation ends with a fatal decision at the top of the tower: the mastermind chooses to leap away from the danger he helped unleash. In the aftermath, the truth about the haunting and the sabotage comes to light, and the station—and the ship it protects—emerge unscathed through a harrowing night of storms, shadows, and revelation.
