As the curtains rise on the fourth chapter of "Plum," Dana Hanlon, portrayed by Jenni Baird, finds herself engrossed in a video montage of her father, whose memories, including those of his own daughter, are slowly slipping away. In the comfort of his abode, Peter Lum (Brendan Cowell) delves deeper into the enigmatic world of CTE. Liz Lombardo (Sara Zwangobani), after scrutinizing Peter's scan results, imparts her findings and inquiries about his adherence to the prescribed medication. To her concern, Peter hasn't even bothered to pick up the prescription, unaware of CTE's relentless progression. He vows to abstain from alcohol until Gavin's return.
Elsewhere, Ainslee (Talijah Blackman-Corowa), bursting with excitement, shares with Gavin (Vincent Miller) her triumph of making the Australian women's hockey team, necessitating an immediate relocation to Perth. Gavin, however, envisioned them moving to Melbourne together, leading to a misunderstanding. Peter and Brick (John Tui) encounter Oliver (Jemaine Clement) and Renee (Asher Keddie), with Oliver inadvertently hinting at Dana's CTE diagnosis. Renee swiftly diverts the conversation, engaging Brick in discussions about Charmayne and their shared project. As they part ways, Oliver and Renee privately debate whether Plum too suffers from CTE, with Renee reminding Oliver of professional boundaries, noting Peter is not his patient.
Ainslee, puzzled by Gavin's reluctance to accompany her, receives a video of the plane incident, mistaking his silence for indifference and storms out. Peter and Brick bond over Gym n’ Trim, but Peter eventually retreats to the solitude of his home, reaching for a drink. Memories of shared camaraderie with Gavin flood back, and his gaze falls upon the unfilled prescription. Meanwhile, Renee ponders over Dana's reflections on CTE. Peter, noticing a missed call from Gavin, attempts to reconnect but to no avail.
Elsewhere, Hugh and Tatiana (Janet Anderson) reflect on their relationship, with Hugh asserting his sincerity, not as a transient visitor but a committed partner. He seeks Peter's plans upon his return, to which Peter reminds him of his continued employment. In a private moment, Hugh pleads with Peter to keep certain matters concealed from Brick and Magic Matt. Peter and Bridget (Crystal Nguyen) find solace in the rhythmic cadence of a man's poem, their conversation swirling with introspective musings. Von steps up next to share his thoughts, and Peter extends an invitation to Bridget for a refreshing swim the following day.
Brick, hoping to lift Charmayne's (Maria Duplaa) spirits, invites her for a beer, mindful of her desire to avoid public scrutiny stemming from the video controversy. Confessing his love, Brick proposes expanding their gym and café venture to the Gold Coast. However, Charmayne decides against it and exits. Plum, prompted to contemplate life, attempts to articulate his understanding through the lens of football terminology. Gavin, drowning in sorrow, turns to alcohol for solace, while Peter retreats into his notebook, penning down his thoughts.
Charmayne awakens in her car, seeking solace in a shower. Peter confides in Bridget about his uncontainable rage, only to be interrupted by Charmayne's return. Peter rushes outside to clarify, introducing Bridget as his friend. Charmayne, inquisitive about the money and having witnessed the video at the airport, reassures Peter that they are a judgment-free zone. Peter admits to losing his airport job, prompting Charmayne to wonder if it was due to intoxication.
She departs, leaving Renee in the lurch as she still awaits a word from Gavin. Convinced that Gavin was deeply affected by witnessing her and Peter in the same space once again, Renee ponders over the silence. Meanwhile, Charmayne dials Renee's number, eager to arrange a face-to-face conversation. Elsewhere, Gavin awakens to find himself sprawled on the cold, hard floor.
Peter, on the other hand, finds solace in the company of Brick, Matt, and Hugh. He prompts them to share their most cherished memory or their deepest regret. Hugh, or perhaps Squeaky, recounts how winning the Merrett Murray Medal stands as his best memory, whereas cashing in his superannuation and squandering it serves as his utmost regret. Matt follows suit, and Brick cherishes the memories of playing alongside Peter. For Peter, the birth of Gavin is etched in his mind as his most precious moment, whereas his biggest regret stems from not reaching out to his father on the day he was drunk and witnessed Peter receive the Australian captaincy. The elder man passed away shortly after, and Peter realized he wasn't any better.
Their reminiscing is interrupted by Dana's entrance into the restaurant. Peter confronts her, questioning her actions. He warns her against causing harm to others. Dana defends herself, stating that she's trying to preserve his legacy. She reveals that her father passed away with unresolved issues, and she intends to conduct a tell-all interview on television. Peter, disgusted, walks away.
Charmayne meets Renee and inquiries about Plum's current state. Renee admits that he's in a mess. Peter and Brick indulge in drugs, reminiscing about their glory days on the field. Brick confesses his love for Charmayne but asserts that he won't act on it. Renee informs Charmayne that they only reached out because Peter has listed her as his next of kin, a decision that puzzles Renee as well but seemingly stems from Peter's brain being affected. Renee speculates that Peter's inability to accept defeat fuels his current state.
As Peter emerges from the bathroom, he's confronted by the apparitions of Charles Bukowski (Matthew Sunderland) and Sylvia Plath (Charlotte Friels), who caution him against returning to the depths of despair, warning of vultures waiting to prey. The bartender observes Peter yelling at an empty space.
Renee and Charmayne's conversation continues, with Renee learning about Peter's erratic behavior. She wonders if Charmayne has ever been jealous of her relationship with Plum. Charmayne reassuringly denies any such feelings. Renee is relieved, asserting that there's nothing romantic between her and Plum. Charmayne believes it's too late for her and Plum, revealing that she slept with Brick. Renee, although shocked, acknowledges that it could have happened.
Charmayne dials Gavin, updating him about Peter's condition and pleading with him to return home. Meanwhile, Peter watches a horse race with a friend, where he's harassed by a man until he loses his temper and strikes him. The entire altercation is captured on video by another bystander.
Renee confides in Charmayne, revealing that she conceived a child at 45, using donor eggs but carrying it to term. Charmayne offers words of comfort, insisting that it's okay. Renee doubts that Plum ever loved her, acknowledging that he is deeply in love with Charmayne.
As Peter wanders the streets solo, shadows of solitude accompany his steps. Awakening from slumber, he's startled to find Sylvia nestled in his bed, her whispers tinged with melancholy as she reveals that poets harbor dark, unseen entities within. Meanwhile, Kaia (Lulu Quirk), with a warm smile, beckons Charmayne indoors. Charmayne enters, confessing to Renee that she's finally seen past the red flags in her relationships and is bound for Argentina to embrace motherhood.
Peter and Sylvia delve into a conversation about her children with Ted Hughes, she painting a picture of Ted as a gentle soul, as fragmented as Peter himself. A man of enigmatic absences, Ted's whereabouts remain a mystery to all. Sylvia, with a gentle nudge, encourages Peter to put pen to paper, to chronicle what he knows with unfiltered honesty. Plagued by self-doubt as a father, Peter's weariness over the lies and deceptions that permeate his life is palpable. They share stories of their fathers, bonding over shared struggles. Sylvia, with heartfelt urgency, implores Peter to pen a letter to his father, believing it's the first step towards healing.
Elsewhere, Brick encounters Dave and recounts the night Plum stood up to a heckler, a moment where Brick acknowledges he never thanked Dave for shielding him from harm. He laments feeling overshadowed by Plum's legendary resilience, feeling like a mere mortal beside an immortal figure. Charles lays it on the line for Sylvia, stressing that this could be their final chance.
As the moment of reckoning nears, Peter steels himself to read the letter aloud to Albert. His voice quivers as he apologizes for their last bitter encounter, pondering why his father turned his back on them. He confesses that even when his father was physically present, a part of him was always missing. Just as Peter's words pour forth, Gavin interrupts, catching him mid-sentence, the letter still clutched in his trembling hand.
