The Duke of Hastings rejects his son Simon after discovering Simon's speech disability persists, declaring the family line cursed.

Simon vows to live as the opposite of his father in every way, including never marrying or continuing the Basset family line.

Daphne Bridgerton reads Lady Whistledown's column announcing that Simon Basset has returned from abroad to claim his dukedom.

Simon and Daphne meet at Lady Danbury's ball after he witnesses Daphne punch an unwanted suitor unconscious.

Simon proposes a fake courtship to Daphne so she will attract better suitors while he escapes pressure to marry.

Anthony Bridgerton reluctantly agrees to support the fake courtship scheme after Simon and Daphne explain their arrangement to him.

Simon and Daphne share their first kiss alone in a secluded garden at Lady Trowbridge's estate.

Anthony discovers Simon and Daphne kissing in the garden, attacks Simon, and demands a duel of honor.

Daphne rides to Regent's Park and interrupts the duel, persuading Simon they must marry to save her reputation.

Simon tells Daphne he cannot have children before agreeing to the marriage, and Daphne accepts his proposal.

Simon and Daphne's wedding ceremony is filled with laughter when Gregory's relentless sneezing disrupts their first married kiss.

The Clyvedon housekeeper tells Daphne about Simon's childhood trauma and his father's impossibly high standards for him.

Daphne initiates sex with the intoxicated Simon and deliberately holds him inside her to try to conceive without his consent.

Daphne and Simon reunite in Hyde Park after she falls from her horse; she tells him she is not pregnant.

Simon and Daphne celebrate the birth of their son David, the new heir to the Hastings dukedom.

Simon Basset, Duke of Hastings, has spent his life vowing never to marry after his father rejected him for his speech disability. When he meets Daphne Bridgerton, the two strike up a fake courtship meant to benefit them both socially, but genuine feelings quickly develop. After being discovered kissing, they are forced into a real marriage that neither fully anticipated. Their honeymoon exposes a devastating deception about children and consent that tears them apart. Both must reckon with their choices before they can build an honest and equal partnership. The birth of their son David marks the joyful resolution of their long road to trust.

The central romance arc of Simon and Daphne.

The Ninth Duke's wife dies in childbirth after defying medical advice, and the Duke rides off to celebrate without mourning her.

An eleven-year-old Simon confronts his estranged father in London and is rejected and ordered away.

Simon plays cards with Anthony Bridgerton at White's club and accepts an invitation to join the Bridgerton family for dinner.

Lady Danbury rescues Simon from a crowd of eager mothers and their daughters at her ball.

Simon makes a formal social call to Bridgerton House with expensive Dutch tulips to reinforce the fiction of his courtship.

Simon presents the tulips to Violet Bridgerton instead of Daphne, moving the widow to tears.

Simon attends the noisy, warm Bridgerton family dinner and is struck by how different it is from his own childhood.

Ten-year-old Hyacinth Bridgerton bluntly announces that Simon does not talk much, discomfiting everyone at the dinner table.

Violet Bridgerton invites Simon to join the family's upcoming boating excursion to Greenwich before he can think to refuse.

Simon joins the Bridgertons on their Greenwich boating trip and picnic, growing increasingly unsettled by Daphne's observations about his past.

Simon coldly shuts down Daphne's remark that he would be a good father, nearly ending their pleasant outing.

Simon gets drunk and starts a brawl with two sailors at a local pub, imagining he is punishing his father.

Simon returns to Clyvedon drunk and tells Daphne she must understand his desperate need to defy his father's legacy.

Simon leaves Clyvedon and sends Daphne a note instructing her to contact him only if she has conceived a child.

Simon and Daphne discover she is unexpectedly pregnant with their fourth child many years into their marriage.

Before Simon ever meets Daphne, his mother dies in childbirth and his father raises him with cold contempt, setting the stage for his later choices. Simon re-enters London society reluctantly, reconnecting with Anthony Bridgerton and attending social events he would rather avoid. His growing involvement with the Bridgerton family — attending their dinner, joining their outings, and charming their mother — draws him deeper into a world he has rejected. After his marriage to Daphne unravels over deception and consent, Simon plunges into self-destruction before Daphne's letter pulls him back toward reconciliation. In the extended epilogue, a late-in-life pregnancy cements the lasting joy of the family Simon once swore never to have.

The social world and secondary scenes shaping the courtship.

The Duke threatens four-year-old Simon for failing to speak, and Simon struggles to stammer a defiant refusal to be hit.

Simon wins a public verbal duel with celebrated dandy Beau Brummel by responding with only the single word 'No.'

Anthony confronts Simon alone in the Bridgerton study and warns him that Simon already knows Daphne wants children and a family.

Daphne asks Anthony why Simon refuses to marry, and Anthony gravely warns her that Simon is simply not meant for her.

The elderly Duke of Middlethorpe approaches Simon at a ball and offers him a cache of letters left by his deceased father.

Simon storms away from Middlethorpe rather than accept the letters, and Daphne reluctantly agrees to safeguard them herself.

Simon tells Daphne that if he could ever choose a wife it would be her, but that marriage to him would destroy her.

Violet gives Daphne a vague and incomplete explanation of sex and reproduction the night before her wedding.

Daphne reveals at the wedding-night inn that she believed Simon was impotent; Simon clarifies he is fully capable of intimacy.

Daphne realizes during lovemaking that Simon has been deliberately withdrawing to prevent conception rather than because he is infertile.

Simon furiously reveals to Daphne that his father told everyone he was dead, and explains his vow to let the family line die.

Daphne locks herself in her private rooms and denies Simon access to her bed, telling him his father still rules him from the grave.

Anthony travels to find Simon and delivers Daphne's letter, urging Simon to consider his responsibilities to his wife's wellbeing.

Simon confesses his fear that a child could inherit his speech disability; Daphne assures him he is nothing like his father.

Simon opens his father's letters, finds only routine estate matters inside, burns them, and declares himself ready for the future.

Simon's childhood is defined by moments of defiance and painful discovery that shape his adult determination to thwart his father's legacy at all costs. As his courtship with Daphne deepens, critical confrontations push both characters toward uncomfortable truths about what they want and what they have kept hidden. Simon conceals his real reasons for refusing marriage while Daphne receives almost no useful information about sex or reproduction before their wedding night. Their honeymoon leads to a chain of betrayals and confessions that force each character to choose honesty over self-protection. Simon ultimately confronts his deepest fears about fatherhood and his own worth, guided by Daphne's steady insistence that he is not his father. When he burns his father's letters unread, he closes the door on the past and steps fully into the life he has chosen.