Ellen Creed, a proud spinster fallen on hard times, has spent the past two years as housekeeper and companion to her old friend Leonora Fiske, a wealthy retiree who in her youth had been a chorus girl “of easy virtue.” Ellen receives a threatening letter warning that unless she can tame her two peculiar sisters, the police will be called and the sisters will be evicted from their lodgings for outlandish behaviour. Leonora allows Ellen to invite her sisters to visit, hoping perhaps for a calmer household and some relief.
One day when Ellen is away, a handsome young stranger, Albert Feather, appears claiming to be Ellen's nephew. Leonora lends him money, but Albert makes her promise not to tell Ellen about either his visit or the loan, and the two keep their agreement hidden from Ellen as she returns with her sisters. The two sisters—Emily Creed and Louisa Creed—soon wear out their welcome, burdening Leonora and her maid, Lucy, with their noisy presence and frayed nerves. Leonora initially vows to turn them out, but Ellen pleads, fearing that her sisters could be sent to an institution. In a moment of rage, Ellen strangles Leonora to death, turning a private catastrophe into a deadly secret.
After the murder, Ellen tells visitors and Lucy that Leonora is traveling, and she convinces her sisters that she has bought the house, ordering them to keep Leonora’s fate to themselves. The stormy weather outside mirrors the growing tension inside as a visit from nearby nuns to borrow lamp oil adds pressure to the fragile arrangement. When Lucy is sent to the shed, she unexpectedly encounters Albert again, who flirts with her and urges secrecy about his presence. Ellen refuses to allow Albert to stay and instead arranges a boat ticket out of the country, even offering him money to begin anew elsewhere.
Albert and Lucy soon uncover that Ellen is hiding more than a simple lie. They find Leonora’s wig, hinting at why the older woman did not travel with it, and a bank blotter that reveals a signature discrepancy on a check tied to Leonora’s name. Albert reads Ellen’s reply about a “sprained wrist,” and suspicion grows. He seduces Lucy in an attempt to seize hidden funds, but the money remains elusive, and the pair’s schemes intensify.
A tense confrontation unfolds as Ellen confesses some of her secrets, while Lucy overhears and flees the house. The arrival of the neighbor nuns forces Albert back into hiding, and Ellen is warned by the police that a man matching Albert’s description is being sought. In a last, decisive move, Albert accepts a final ticket and the money Ellen had prepared for his departure, slipping away as Ellen’s world tilts between fear and relief.
As the fog closes in, Ellen’s two sisters return from a walk to report they had seen Albert playing tag with two men. With a sly, knowing smile, Ellen dresses for departure, bids her sisters a quiet farewell, and steps out into the night, leaving the house and its secrets behind to seek the company of “some men” she hopes will change her fortunes.
