"The Shadows of the Starstone!"
Surviving the horrors of Starkesboro by no means affords Doctor Strange any rest or relaxation. He must follow the trail of ancient evil leading ultimately to Shuma-Gorath, he who sleeps - but shall awake.
The itinerary leads on to the British Isles; precisely Penmallow, Cornwall, England. Here, Henry Gordon has come to claim his inheritance. The heirloom turns out to be a latter-day haunted house atop a hill.
Gordon is greeted at the door by a furtive young woman introducing herself as 'Blondine'. Blondine is the caretaker of Witch House, as the ancestral dwelling is referred to locally.
Gordon immerses himself in the library, motivated by curiosity aroused by the ancient occult tomes populating the shelves. He learns of the lost city, Kalumesh. Sunk beneath the waves eons ago. Like Starkesboro, the people of this forgotten city worshipped a Demon in service to Shuma-Gorath. Their deity-of-choice was Dagoth.
The next morning, Henry Gordon takes Blondine out in a speedboat off the coast waters. Daydreaming about untold riches in gold and jewels, Gordon is unprepared for what he and Blondine discover, scuba-diving underwater.
The Demon, Dagoth holds the pair transfixed with terror at his macabre majesty. Doctor Strange's mystic senses are attuned to the arcane energies emitted by such a primal force of evil. Fortuitously, he is swooping overhead
and dives headlong into the ocean to rescue the hapless pair.
Strange subdues Dagoth with the Rings of Raggador and flies Gordon and Blondine back to Witch House. Using the Eye of Agamotto to probe Blondine's memory, Strange learns of the histories of Kalumesh and Dagoth. Blondine is the reincarnation of a high priestess who committed blood sacrifices in Dagoth's dread name.
Blondine remains in a trance-mode and involuntarily releases a cascade of eldritch electrons that rain all over Penmallow. One by one, the citizens leave the comfort of their homes to file obliviously forward, to the sea. Called to their doom by Dagoth, who has freed himself from Doctor Strange's confinement.
Even Strange himself is captivated by the Demon's spell. It takes Clea's intervention to stop him joining the others walking to their deaths in the sea. Strange is angered by his own susceptibility to Dagoth's influence and uses this rage to dispense with the Demon lackey.
Strange and his associates journey back to Witch House, where fresh horror awaits them.
Aside: The first speech bubble in this issue is "What is it that disturbs you, Stephen?" became the title of a one-shot 1997 Doctor Strange story by this issue's penciller, P. Craig Russell.