Dear Mr. Prohack

Arthur Prohack inherits £250,000 from an unexpected windfall and immediately takes six months' sick leave from his Treasury post. The windfall unsettles his famously frugal habits and prompts everyone at home to rethink how they might use the money. His absence sets off a chain of plans and temptations as the family begins to press him for financial favors.

Mary requests funds for a theatrical production, while Charles seeks investment capital from his father for a risky scheme. Eve spends the windfall on a much larger house, filling it with an aviary and aquariums. The combined requests illustrate how wealth unsettles the family and invites over-ambitious plans.

Charles buys his father a new car, and on its first drive the vehicle is involved in an accident with Mimi Warburton. The crash unsettles the household and draws Mimi more directly into Arthur’s orbit. It also foreshadows the tangled loyalties to come.

Initially frosty, Arthur takes Mimi Warburton on as his private secretary. Mimi’s presence intensifies the office politics surrounding the fortune and begins to blur professional boundaries. Her involvement pulls both father and son deeper into wealth’s complications.

Charles cancels a meeting with Arthur and arranges a board meeting without him. In revenge, Mimi arranges for Arthur to attend Charles' place at a meeting with Lady Maslam, Charles' patroness. The move deepens the strain between father and son and pulls Arthur further into Lady Maslam’s circle.

Left behind at home, Charles and Mimi lunch together and fall in love. Mimi then tries to resign, noting she had promised not to fall for Charles, but the romance persists. The affair threatens both their positions and the integrity of Arthur’s household finances.

Spinner arranges to invest part of Arthur's money, hoping to grow the fortune, while Eve stages an elaborate party to celebrate Mary's engagement to Oswald Morfrey. The juxtaposition of high-risk finance and festive excess highlights the volatility wealth creates in the family. Arthur watches these developments with mounting unease.

Mary and Oswald run away together and marry without their parents’ knowledge. Arthur hunts them down, but Oswald refuses his help. The secret union complicates the parents' expectations and the fate of the fortune.

Spinner informs Arthur that a run on the stock market could ruin the money invested. Arthur weighs the risk as the fortune’s value wobbles and his family’s plans hang in the balance. The warning intensifies the tension between prudence and speculation.

Mimi discovers that the investment scheme is about to collapse and argues with Arthur at Lady Maslam's home. The confrontation forces Arthur to reassess whom he can trust and the true cost of wealth. Their discussion ricochets through the social circle around Lady Maslam.

Arthur falls ill with a cold and drifts into a fever dream inspired by Arthurian legends, broadcast on the BBC Third Programme. The surreal dream magnifies the episode of sudden wealth and moral risk. It foreshadows the revelations to come when he awakes.

Mimi wakes Arthur with news that Charles has broken up with her and plans to flee to Paris with Lady Maslam. It turns out to be a misunderstanding: Charles has not boarded the plane and returns home with Arthur to propose to Mimi. The mix of romance and miscommunication underscores the fragility of the fortune’s temptations.

Spinner’s advice seems to ruin Charles’ scheme, but he avoids the crash and makes Arthur another £250,000. The extra windfall loosens Arthur’s ties to his frugal principles even as he contemplates the costs. The money seems to multiply while the personal costs keep mounting.

Arthur reconciles with Eve and plans to move back to their old house. He also resolves to help Oswald, Mary, and Charles secure more stable homes and healthier futures. The family begins to turn away from reckless wealth toward practical care.

Returning to work, Arthur donates the new £250,000 anonymously to the Treasury under the guise of a massive repayment of back taxes. The donation restores the balance between wealth and the public purse. It marks a quiet, principled end to his experiment with fortune.