The story revolves around Sir Claude Mulhammer, a prosperous financier, who finds himself entangled in a web of familial secrets and unexpected revelations. His old confidential clerk, Eggerson, is called upon to assist in a delicate task involving Lady Elizabeth and a new young employee, Colby Simpkins. As layers of hidden identities unravel, each character must navigate through surprise, disappointment, and newfound connections to form an unconventional family.

An Unexpected Introduction

Sir Claude Mulhammer, a shrewd middle-aged financier, invites his retired confidential clerk, Eggerson, to his home in London. The reason is clear-cut: Eggerson is to meet Lady Elizabeth’s plane from her Swiss trip and inform her of a change in staffing. A young man named Colby Simpkins has replaced Eggerson, and Sir Claude hopes Lady Elizabeth will come to like Colby enough to eventually adopt him, perhaps as a replacement for a son she had to give away in her youth. However, this plan hinges on keeping Colby’s true identity as Sir Claude’s illegitimate son a secret until Lady Elizabeth has accepted him.

Surprises at Home

Before Eggerson can depart for the airport, Lady Elizabeth arrives unexpectedly, necessitating an immediate and unplanned introduction to Colby. Surprisingly, she recalls recommending Colby herself and, driven by her spiritual interests, she warmly embraces him into the household. Colby quickly becomes a favorite among the members of the household, including Sir Claude’s daughter, Lucasta, and her fiancé, B. Kaghan.

Shared Interests and Secrets

As a struggling musician, Colby consents to share his passion for music with Lucasta. In a moment of candid conversation at his new flat, which Sir Claude has secured for him and Lady Elizabeth has offered to decorate, Colby and Lucasta find an unexpected mutual affection. Lucasta, who is beginning to reassess her feelings for Kaghan, confides in Colby that she is Sir Claude’s daughter. This revelation stuns Colby, as it means she is his half-sister, yet he is unable to disclose this knowledge to her. Misinterpreting his reaction, Lucasta returns to Kaghan, reaffirming her engagement.

Questions and Confessions

Lady Elizabeth, after ushering Lucasta and Kaghan out, delves into Colby’s past. Learning he was raised in Teddington by an aunt, Mrs. Guzzard, she becomes convinced he is the son she had in her youth, whom she had given up and who was subsequently adopted by a uniquely-named couple from Teddington. Unable to share her suspicions with Colby, he remains puzzled by her intense interest in his history. When Sir Claude joins them, Lady Elizabeth declares her conviction that Colby is her long-lost son.

Confronting the Truth

Sir Claude realizes the need to disclose the truth about Colby’s lineage, but Lady Elizabeth is unwavering in her belief. Frustrated by the conflicting parental claims, Colby insists on uncovering his true identity. They agree to summon Mrs. Guzzard for clarification.

Revelations and Realizations

Sir Claude schedules a meeting in his office, during which he and Lady Elizabeth engage in an honest conversation, deepening their understanding of each other. Upon Eggerson’s arrival, alongside an unexpected Lucasta, the meeting takes an unexpected turn. Sir Claude informs Lucasta of her kinship with Colby, leading her to comprehend Colby’s earlier reaction and to officially announce her bond with Kaghan.

The Unfolding of Truth

Mrs. Guzzard, escorted by Kaghan, reveals startling truths during Eggerson's inquiry. She discloses that Kaghan is actually the son Lady Elizabeth had given up, having stayed with the Guzzards before his adoption by the Kaghan family. Further, Mrs. Guzzard reveals that her sister, who was expecting Sir Claude’s child, died before childbirth, and that Colby is her biological son. She admits to allowing Sir...