Professor Parkin, a stuffy Cambridge academic, arrives for an off-season stay at a hotel somewhere on the English east coast. Preferring to keep to himself, Parkin spends his stay walking along the beach and visits a local graveyard, which has become overgrown and unkempt. While there, he spots a small object protruding from a grave which is partly undermined by the edge of the cliff. He uncovers it and finds it is a bone whistle, which he keeps. When walking back along the shore, he turns twice and sees a dark silhouetted figure standing still in the distance in front of a setting sun, appearing to watch him.
Later, in the calm of his hotel room, he cleans and inspects the whistle, revealing a carved inscription: "Quis est iste qui venit" ("Who is this who is coming?"). He blows the whistle and a windstorm begins outside. Later that night, Parkin is kept awake by mysterious noises in his hotel room.
At breakfast the following morning, another guest at the hotel asks Parkin if he believes in ghosts. Parkin responds in a typically academic fashion, dismissing such beliefs as little more than superstition. However, that night, Parkin appears to have disturbing dreams of a spectre pursuing him on the beach. His nerves are not helped when, the following morning, he is informed by a maid that both of the beds in his room have been slept in – even though Parkin only slept in one.
Increasingly disturbed, he searches a book for answers. That night, he is awakened by a sound like flapping sheets. As he sits up in bed, the sheets from the other bed across the room move and then rise up into the phantom from the shore. Waking another hotel guest who comes to his aid, Parkin sits in stunned terror at what he has just witnessed.