A Sociopath’s Guide to a Successful Marriage Summary Chapter by Chapter | MK Oliver
Introduction to A Sociopath’s Guide to a Successful Marriage (Chapter-by-Chapter Summary)
What would you do to protect the perfect life you’ve built—the Hampstead dream, the private schools, the bespoke kitchen, the admiring glances at the school gates?
Would you hide a body before your son’s fourth birthday party?
Would you poison your mother-in-law with foxglove tea?
Would you electrocute a man in a urinal?
For Lalla Rook, the unforgettable narrator of MK Oliver’s darkly comic debut, these aren’t hypothetical questions. They’re just items on a to-do list.
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Book Structure Overview
A Sociopath’s Guide to a Successful Marriage is structured around five parts, each representing a stage in Lalla Rook’s psychological recalibration as she navigates murder, blackmail, and the cutthroat world of North London parenting.
| Section | Chapter Range | Key Focus |
|---|---|---|
| Part One: Relapse | Chapters 1–26 | The murder of Jason Mercer and the cover-up |
| Part Two: Recalibrate | Chapters 27–36 | Lalla’s past as “Lola Wells” and poisoning Madeleine |
| Part Three: Reconnect | Chapters 37–54 | The return of Matthew Hollis and blackmailing the elite |
| Part Four: Revive | Chapters 55–74 | Saving the marriage and discovering Stephen’s affair |
| Part Five: Renew | Chapters 75–85 | The final showdown and Lalla’s total social victory |
| Epilogue | Chapter 86 | Lalla’s reflection as a billionaire CEO |
Total Chapters: 86 numbered chapters
Parts: 5 (Relapse, Recalibrate, Reconnect, Revive, Renew)
Prologue: None
Epilogue: Yes (Chapter 86)
Point of View: First-person narrative from Lalla Rook
The narrative follows a linear progression through Lalla’s increasingly complex schemes, though it’s enriched by her cold internal monologues and strategic flashbacks to her traumatic childhood as Lola Wells.
Book Table of Contents
Part One: Relapse (Chapters 1–26)
Part Two: Recalibrate (Chapters 27–36)
Part Three: Reconnect (Chapters 37–54)
Part Four: Revive (Chapters 55–74)
Part Five: Renew (Chapters 75–85)
Epilogue (Chapter 86)
A Similar Read: Want to Know a Secret? Summary Chapter by Chapter | Freida McFadden
A Sociopath’s Guide to a Successful Marriage Summary Chapter by Chapter
⚠️ Spoiler Warning: This section contains detailed, chapter-by-chapter plot summaries that reveal key plot points and character developments.
Part One: Relapse
Chapter 1: Visitor
Lalla stabs an intruder seven times minutes before her son’s birthday party and hides the body behind a sealed door. She proceeds with the party to avoid social embarrassment.
Chapter 2: Monsters
Lalla manages party guests while her son struggles, admitting she finds bonding with her children difficult. When a child tries to enter the room with the corpse, she tells him a monster lives inside.
Chapter 3: Chablis
The mothers gather in the kitchen drinking wine while discussing their husbands’ inadequacies. Cait arrives distraught after receiving a threatening text from her abusive husband Owen.
Chapter 4: Owen
Cait reveals Owen broke into her house and texted a photo of her sleeping as a threat. Lalla begins to wonder if the dead man was more than just a burglar.
Chapter 5: Rabbit
Cait discovers blood outside the living room door and screams in terror. Lalla invents a lie about the cat disembowelling a pet rabbit to explain the carnage.
Chapter 6: Hamster
At school pickup, Lalla learns her daughter Nelly drowned the class hamster and smiled when told it was dead. Lalla recognizes her daughter is “not like other children.”

Chapter 7: Tapping
Lalla searches the corpse and finds a phone and car key fob. As she wraps the body, she hears three sharp taps on the window.
Chapter 8: Corpse
Cait has seen Lalla wrapping the body and becomes fascinated by the corpse, counting the seven knife wounds.
Chapter 9: Soap
Lalla forces Cait to touch the murder weapon, making her an accomplice. Cait runs from the house in panic with blood on her hands.
Chapter 10: Wrapping
Lalla moves the body to the garage using the gardener’s wheelbarrow. She cooks dinner and ticks items off her mental to-do list.
Chapter 11: Fathers
Stephen is depressed at dinner, focused on his late father. Lalla suspects he’s hiding something and notices him constantly checking his phone.
Chapter 12: Cul-de-Sac
Lalla reflects that married love is a “rational business choice” based on status. She has sex with drunk Stephen but finds his effort lacklustre.
Chapter 13: Toyota
Lalla finds the intruder’s blue Toyota Corolla and moves the corpse to her Porsche boot. She sprinkles it with patio cleaner to hide the smell.
Chapter 14: Hampstead
Lalla views an £8 million Victorian villa and imagines its pool as a perfect burial site. She thinks about drowning her mother-in-law there.
Chapter 15: Tor
Lalla visits wealthy friend Tor and checks her Ring footage, seeing the intruder scoping her house. She realizes the dead man was stalking her.
Chapter 16: Accomplice
Lalla tells Cait the body is in her Porsche and stages a fake 999 call to frighten her. Cait agrees to help dispose of the body.
Chapter 17: Concrete
Lalla learns concrete stays malleable for only a few hours. She plans to bury Mercer under Tor’s new pool house.
Chapter 18: Letter
Stephen reveals police are looking for missing man Jason Mercer, a disgraced cop. He received an anonymous note saying “Your wife isn’t who she says she is.”
Chapter 20: Uniform
When a woman steals Lalla’s parking space, she keys the Jaguar and stabs its tyre. Lalla notes that “every tiny advantage matters.”
Chapter 21: Adams
Lalla bribes Nelly to enter Adams Prep and swaps her daughter’s Play-Doh with another child’s. The teachers praise Nelly’s work.
Chapter 22: Police
Detectives interview Lalla about Mercer, finding her name in his desk. After they leave, one detective says she’s “guilty as hell.”
Chapter 23: Research
Lalla and Cait discover Mercer was a serial sex attacker. Police had an anonymous tip about Mercer being at Lalla’s house.
Chapter 24: Aimée
Lalla offers the nanny extra money to flirt with Stephen, hoping to boost his testosterone. She views this as “recharging a flat battery.”
Chapter 25: Suspicions
Lalla concludes Madeleine hired Mercer and goes to plant evidence in Cait’s house. She finds Cait’s bed soaked in petrol and is confronted by Owen.
Chapter 26: Matches
Owen attacks Lalla on a petrol-soaked bed, but she steals his matches and drops one. She watches him burn without remorse.
Part Two: Recalibrate
Chapter 27: Laughter
Lalla meets friends while the neighborhood buzzes about Cait’s house fire. Cait arrives looking wild-eyed, having lost everything.
Chapter 28: Insurance
Cait’s house burned down with Owen’s body inside, but his insurance had lapsed. A body was found in the fire.
Chapter 29: Ponchos
Lalla receives a 1999 clipping about “Lola Wells,” whose mother stabbed her father. She decodes a meeting location.
Chapter 30: Burnt
Aisha’s husband wants to move to Abu Dhabi. Police have found an accelerant and believe Cait’s fire was arson.
Chapter 31: Hammer
When the headmistress rejects Nelly, Lalla places a hammer on her desk. Terrified, the headmistress agrees to let Nelly sit the exam.
Chapter 32: Austen
Lalla raids Stephen’s savings and rubs testosterone gel on him while he sleeps. Her to-do list includes “killing Hollis.”
Chapter 33: Madeleine
Lalla visits her mother-in-law and slips crushed foxglove leaves into her tea. Madeleine reveals she knows Lalla is actually Lola Wells.
Chapter 34: Cocktails
Tor reveals she’s being blackmailed over videos with her young lover. Stephen texts that Madeleine has had a stroke.
Chapter 35: Mother
Stephen is frantic as Madeleine lies in intensive care. Lalla steals £200,000 from his savings and destroys the foxglove leaves.
Chapter 36: Pancho’s
Lalla meets “MonkeyWarrior” at a café: Matthew Hollis, her first husband. She pushed him off a mountain and he survived.
Part Three: Reconnect
Chapter 37: Rocks
Lalla recalls pushing Hollis off Mont Blanc. She realizes her current marriage is bigamous and considers killing him again.
Chapter 38: Bob’s
Tor needs £10,000 for blackmail. Cait has been arrested for Owen’s murder.
Chapter 39: Vampires
The estate agent demands a £400,000 deposit. Lalla’s marriage to Stephen is legally void.
Chapter 40: Hollis
Lalla visits Hollis’s sad flat and pretends to have amnesia. He hired Mercer to track her down.
Chapter 41: Charged
Police reveal Mercer photographed Lalla for weeks. Tor is paying a lawyer for Cait’s bail.
Chapter 42: Bronzefield
Lalla visits Cait in prison, who now calls herself “Flame.” Cait hasn’t told police about Mercer.
Chapter 43: Nativity
At the school play, Nelly unfurls a banner saying “SANTA’S DEAD.” Lalla notes her handwriting is “impressively neat.”
Chapter 44: Feet
Lalla gets a pedicure while Cait calls from prison with new theories. Cait is thriving in prison.
Chapter 45: Partnership
Lalla meets Josh Krill at the Ritz and threatens to expose his abuse of women. She demands he make Stephen a partner.
Chapter 46: Memories
Hollis shows Lalla his Pardini pistol. She tries to kill him with a hammer but finds her arm won’t move.
Chapter 47: Beaufort
Lalla goes to the Savoy to entrap Zac, Tor’s blackmailer. They agree to go back to his apartment.
Chapter 48: Zac
Lalla ties Zac to the bed and steals his laptop. She finds the sex tapes of Tor and other women.
Chapter 49: Video
Lalla steals £150,000 in Bitcoin from Zac and finds a sex tape of Tor’s husband Lawrence. She posts a mysterious image to taunt Tor.
Chapter 50: Bail
Cait is released on bail but banned from the pre-school. Police question Lalla about the Bitcoin transfer.
Chapter 51: FOG
Hollis tells Lalla that Stephen is cheating on her every Sunday. She must either win Stephen back or commit to Hollis.
Chapter 52: Unfaithful
Lalla creates an Excel spreadsheet tracking her sex life with Stephen. She confirms he never has sex on Sundays.
Chapter 53: Identity
Lalla tells Cait that Hollis is a “contract killer” who murdered Owen. She avoids a call from the fertility doctor.
Chapter 54: Wolseley
Stephen takes Lalla to dinner but reveals he didn’t make partner. He asks for a divorce.
Part Four: Revive
Chapter 55: Christmas
Lalla vandalizes Stephen’s belongings and the children start a fire. She creates a resolution list to save her marriage.
Chapter 56: Stalking
Lalla takes Cait to stalk Hollis at a rifle club. She plants evidence in his car to frame him.
Chapter 57: Revenge
Tor is terrified of being exposed on Facebook. Lalla watches her friend’s anxiety with satisfaction.
Chapter 58: Divorce
Hollis arrives with flowers while Stephen watches. Lalla tells Stephen she’s pregnant to trap him.
Chapter 59: Law
Lalla meets Lawrence in the House of Commons and blackmails him for £50,000. She uses the money for the house deposit.
Chapter 60: Mother-in-Law
Lalla visits Madeleine in the hospital and pulls out her cannula. Madeleine calls her children a “simpleton” and “maniac.”
Chapter 61: Headmistress
Lalla drives to the headmistress’s house in pyjamas and stuffs cash through the letterbox. The police are called.
Chapter 62: Supermarket
Lalla tracks Stephen to a Tesco car park and sees him with Georgie, his former fiancée. She lets down his tyres.
Chapter 63: Blackmailing
Nelly is sent home for stapling a girl to her seat. Lalla tells Tor that Zac was scamming her all along.
Chapter 64: Laboratory
Lalla confronts Georgie, who admits the affair has lasted four years. Lalla feels a rare sense of shame.
Chapter 65: Surveillance
Cait’s electronic tag gives Lalla an idea to frame her. Krill attempts to counter-blackmail Lalla.
Chapter 66: Georgie
Lalla meets Georgie in Soho and learns about the Cotswolds wedding plans. She decides to break into Georgie’s house.
Chapter 67: Favour
Lalla bribes builders to keep Mercer’s body buried. She blackmails Tor into swapping exam numbers with Nelly.
Chapter 68: Resignation
Lalla locks Stephen in the cellar. He admits he’s in love with Georgie.
Chapter 69: Test
Lalla forces Stephen to attend Nelly’s exam. She tells Nelly not to write her name on the paper.
Chapter 70: Gone
Police reveal they found Zac and that Hollis paid Mercer. Lalla must “delete Hollis” before he talks.
Chapter 71: Teddy
Krill demands sex or he’ll release the blackmail tape. Lalla breaks into Georgie’s house and steals her diary.
Chapter 72: Georgie
Lalla prepares a “suicide scene” for Georgie but feels a rare moral qualm. She takes the diary and teddy bear instead.
Chapter 73: Electricity
Lalla follows Krill to a bar and electrifies the urinal while he uses it. He’s severely burned but alive.
Chapter 74: Strand
Hollis proposes with a £100,000 ring and reveals he’s a billionaire CEO. Lalla embraces her “billionaire husband.”
Part Five: Renew
Chapter 75: Desk
Stephen has jimmied open Lalla’s desk and found her to-do lists. He calls her a “fucking robot.”
Chapter 76: Bigamist
Lalla tells Stephen about her marriage to Hollis. He’s delighted he can marry Georgie without a settlement.
Chapter 77: Proposal
Hollis admits he wrote a new will excluding Lalla. He asks for honesty about the “accident” on the mountain.
Chapter 78: Push
Hollis pulls a pistol and confronts Lalla at the river. He prepares to drop her into the Thames.
Chapter 79: Fate
Cait appears and pushes Hollis and his wheelchair into the river. Lalla tells her to burn his will.
Chapter 80: Hospital
Hollis is in a critical coma. Lalla tells police he was an abusive estranged husband.
Chapter 81: Results
Nelly is rejected from Adams Prep. Hollis dies, and Lalla inherits his billion-dollar fortune.
Chapter 82: Gloating
Madeleine visits to gloat but Lalla reveals she gave Georgie’s diary to Stephen. Madeleine is outflanked.
Chapter 83: Letter
Cait writes from prison enjoying her infamy. Lalla forges an acceptance letter for Nelly.
Chapter 84: Acceptance
Lalla calls Adams pretending to be Sophie and accepts Nelly’s place. Police conclude Hollis killed Mercer.
Chapter 85: Reader
Stephen apologizes and wants to reunite. They decide to “wed again” and move to Hampstead.
Chapter 86: Epilogue (Claridge’s)
Lalla is now PTA chair and a billionaire CEO. She eyes a new mansion in Kensington, already planning her next move.
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