The Bliss of Mrs. Blossom

Robert Blossom runs a brassiere manufacturing business with relentless dedication, yet he secretly conducts imaginary orchestras in his home, nurturing a deep passion for music. His workaholic routine keeps him from fully pursuing his artistic dream. The tension between duty and longing sets the stage for the family's complicated dynamics.

Harriet, a romantic-minded painter, is touched by Ambrose Tuttle's down-on-his-luck backstory when he repairs the broken sewing machine. She feels a powerful, immediate connection and begins to fall for him. Ambrose, meanwhile, is drawn into the Blossom home and the promise of affection.

Harriet and Ambrose become lovers, an affair dramatized by a fantasy sequence where Ambrose appears as a heroic rescuer. The chemistry grows as Harriet experiences a surge of romance she has long yearned for. The relationship introduces tension with Robert when he returns.

When Robert arrives home unexpectedly, Harriet hides Ambrose in the attic and tells him to leave in the middle of the night. Ambrose becomes Harriet's secret paramour, and the two begin a day-to-day affair away from prying eyes. Harriet also begins to educate Ambrose privately, turning the attic into a makeshift living space.

Ambrose, inspired by Teach Yourself books provided by Harriet, expands his plans to influence the household and remain in Harriet's life. He grows to care for both Harriet and Robert, feeling guilty for the emotional turmoil he has caused. The attic-based arrangement becomes a semi-permanent feature within the home.

Ambrose is reported missing, and Detective Sergeant Dylan from Scotland Yard is assigned to the case. His inquiries quickly cast suspicion on Harriet and her household. Harriet denies Ambrose's presence, and Dylan catches her near-misses, including a disguise when Ambrose appears as 'Juan' and Harriet calls him her half-brother.

Dylan grows convinced Harriet is having an affair with her supposed half-brother and that 'Juan' helped her commit murder. He continues to press, hoping to trap Harriet in a falsehood. The investigation strains the family as the attic tale remains unresolved.

Robert hears unsettling noises from the attic and suspects someone is living there, only to be convinced by Harriet that it is his imagination. Harriet's manipulation keeps him from confronting the truth. His grip on reality loosens as the mystery deepens.

Ambrose uses his new education to quietly advise Robert, steering him toward business diversification. The advice pays off as Robert's fortunes grow beyond his dreams. The sudden wealth inspires Robert to retire early and devote himself to music.

On the eve of Robert's retirement, Dylan returns and declares that Ambrose's disappearance has been solved. He believes Harriet is sheltering a secret lover in the attic, 'Juan'. Robert and Harriet confront the attic, only to discover Ambrose alive and well.

Robert and Harriet go to court to divorce, and Robert makes a surprising gesture by giving his businesses to Harriet and Ambrose as a wedding gift. The arrangement aims to secure a life for Harriet and Ambrose while Robert pursues his music. The court decision marks a turning point in their relationships.

Some time later, Ambrose arrives for breakfast in sober office attire and leaves Harriet to attend to business. Harriet stamps on the floor, and Robert rises from the basement in a mod outfit, signaling a renewed, unconventional union rooted in music. The trio's dynamic settles into a strange, hopeful rhythm as they embrace.