Julian writes his loneliness in a green notebook titled 'The Authenticity Project' and leaves it in Monica's café.

Monica tracks down elderly artist Julian Jessop at a cemetery after reading his heartfelt notebook entry.

Julian visits Monica's café in response to her artist advertisement and accepts her offer to teach art classes.

Hazard finds the green notebook at a bar and reads the intimate entries from Julian and Monica.

Hazard travels to Thailand to get sober, grows restless, and decides to fly back to London.

A charming Australian named Riley attends one of Julian's art classes and begins falling for Monica.

Hazard arrives unannounced at Monica's Christmas celebration, reuniting with Riley and shocking everyone present.

Monica realizes Riley knew about her from the notebook all along and kicks everyone out of the café.

Alice finds the green notebook in her bag during a family argument and reads all the entries inside.

Riley and Hazard find Julian cold and confused inside his locked house and break in to rescue him.

Monica decides to restart the canceled art classes, and both Alice and Hazard join the group.

Julian's wife Mary walks into the party his friends threw in her memory, revealing she is alive.

Monica tells Riley she is not in love with him and ends their relationship.

Monica finds Hazard waiting at the Admiral's grave, they kiss, and go home together.

Julian dies peacefully in a park after his birthday party; a stranger named Dave finds the notebook beside him.

Julian, a lonely aging artist, writes his story in a green notebook and leaves it in a café, hoping to create a genuine human connection. Monica, the café owner, finds the notebook and tracks Julian down, convincing him to teach art classes that revive his sense of purpose. A charming Australian named Riley falls for Monica after receiving the notebook from Hazard, but his secret knowledge of her creates a devastating rift when she discovers the truth. The group fractures but reunites to save Julian from a dangerous depression, deepening their bonds as a community. A dramatic party reveals that Julian's wife Mary is alive, prompting Monica to end things with Riley and eventually open herself to love with Hazard. Julian dies peacefully after his birthday surrounded by people who love him, and a stranger named Dave finds the notebook, giving the project a chance to begin again.

The notebook's journey from Julian's hands to Dave's.

Monica quits her corporate law career and uses a relative's inheritance to open her own café.

Hazard snorts cocaine using his rolled-up resignation letter moments before finding the notebook at a bar.

Hazard interviews a divorced Englishman named Roderick in Thailand as a potential match for Monica but disqualifies him.

Monica and Riley visit Borough Market together and Riley kisses Monica on London Bridge.

Julian hosts a tea party at his home, where Riley offers to help him sell old belongings online.

Monica's café thrives financially for the first time as Julian's art classes attract new business to the space.

Alice, a struggling young mother and Instagram influencer, watches Monica and Riley dancing inside the café from the cold street.

Julian gifts Monica an oil-painted portrait of her at the Christmas lunch gathering at the café.

Alice visits the café to find Monica crying after Christmas but leaves after Monica rejects the notebook.

The group travels to Paris together on an art class trip, joined by Alice, Hazard, and Betty.

Betty is mugged during the Paris trip and Benji chases down the thief, earning Betty's genuine respect.

Alice photographs Julian in his eclectic outfit and sets up an Instagram account that rapidly grows his fame.

Hazard begins volunteering at the Mummy's Little Helper charity and develops a business idea to train the mothers as gardeners.

Hazard beats Monica at backgammon and she agrees, as per their wager, to be his date at a wedding.

Monica hosts Julian's birthday dinner club at the café and presents him with the green notebook as a parting gift.

Monica left a secure legal career and used a relative's inheritance to open her own café, trading stability for purpose but finding herself lonely and financially stretched. While Hazard struggled with his addiction and Hazard screened unsuitable men in Thailand, the characters around him navigated their own quieter conflicts — Riley kissing Monica on London Bridge, Julian inadvertently outing Baz's relationship, and Alice watching Monica's life from the cold street and wishing she had it. Secondary events on the group's Paris trip deepened friendships and gave Julian renewed fame through Alice's Instagram work. Hazard's growing involvement in a local charity and a strategic backgammon game inched him closer to Monica. The pool closes with Monica gifting Julian the notebook at his birthday dinner, a gesture of trust that brings his arc full circle.

The quieter moments that shaped the lives behind the notebook.

Monica writes her own confessional entry in the notebook about her longing for love and family, then leaves it in a restaurant.

Hazard tries to return the notebook to Monica's café but stops when he recognizes her as the woman he had cursed.

Hazard writes his own entry in the green notebook while on the island in Thailand.

Riley finds the green notebook in his backpack on the flight to England and reads through all the entries.

Riley feels guilty for knowing Monica's private feelings through the notebook and writes his own entry inside it.

Monica and Riley dance playfully in the snow outside the café while Alice watches from the street, wishing she were Monica.

Baz confronts Julian at the Christmas lunch for revealing his relationship with Benji to Betty and storms out.

Hazard and Riley meet at the Admiral's grave on New Year's Day and go together to find Monica to help Julian.

Hazard relapses at the wedding, getting drunk and snorting cocaine despite his commitment to sobriety.

Monica reveals her childhood OCD to Hazard the morning after his relapse and they agree to start over.

Lizzie finds the notebook at the charity center, reads all the entries, and sends it to Julian's wife Mary with a note exposing his deception.

Julian admits to his friends gathered at the party that he lied about Mary dying to avoid confronting his past.

Mary visits Monica's café and tells her it is Hazard, not Riley, who is in love with her.

Alice tells Max their marriage is not working, he agrees and insults her, and she walks out on him.

Baz and Benji announce their engagement to the group at Julian's birthday party celebration.

The story's emotional hinge points begin with Monica writing her own confessional entry and passing the notebook on, and Riley discovering it mid-flight and feeling guilt-ridden for knowing Monica's private thoughts. Early fractures — Baz confronting Julian for exposing his relationship — are matched by the group's quiet reunions, most significantly when Hazard and Riley find each other on New Year's Day and join forces to rescue Julian. Hazard's relapse at the wedding forces the truth about his addiction into the open and ultimately brings him and Monica closer, culminating in her rare disclosure about her childhood OCD. Lizzie's decision to send the notebook to Julian's real wife Mary sets off the novel's biggest revelation and opens the door for multiple characters to stop living behind their constructed facades. The pool closes on new beginnings: Alice's departure from her marriage and the announcement of Baz and Benji's engagement signal that authentic lives are finally within reach.