Breaking Down the Devastating Ending of All Her Fault

By the end of the eight-episode series All Her Fault, long-held secrets are revealed as Carrie Finch (Sophia Lillis) confronts the Irvine family with a gun. The show delves into how love can become controlling and the lengths parents will go to for their children. The finale doesn’t just solve the mystery of Milo Irvine’s (Duke McCloud) disappearance after a playdate; it uncovers the underlying crime that led to his abduction and then asks a difficult question: what does justice look like when the person you need to escape is the person you trust most?

Peacock’s limited series, The Peacock, centers on the Irvine family, a wealthy Chicago family thrown into turmoil when their son, Milo, goes missing. As Marissa (Sarah Snook) frantically searches for him, the show evolves from a suspenseful thriller into an exploration of honesty, power dynamics, and the extreme measures parents will take to safeguard their families and lifestyles. It’s based on the novel by Andrea Mara.

“It’s incredibly gripping,” explains executive producer Nigel Marchant. “The show immediately puts you right into a terrifying situation – every parent’s biggest fear.”

The night that breaks everything open

The story starts on a calm afternoon in Chicago when Marissa goes to Jenny Kaminski’s (Dakota Fanning) house to get Milo, but he’s nowhere to be found. Jenny claims she didn’t schedule a visit, and worry quickly sets in. What initially seems like a simple case of a missing child soon unfolds into a much more disturbing story about the dangers of obsessive love.

As the investigation continues, police learn that Jenny’s nanny, Carrie Finch, was the one picking up Milo from school. Video footage then reveals Carrie arguing with her ex-boyfriend, Kyle Smith (Dominic Masterson), at the Chicago Marathon, suggesting she had an accomplice. Realizing Kyle’s identity is about to be uncovered, Carrie takes Milo to hide with her father, Rob (Erroll Shand), at his motel.

Carrie arrives at the Irvines’ home and reveals a shocking truth: she’s actually Josephine Murphy, the woman who was in a car accident with Peter and Marissa six years ago. While Marissa is completely surprised, Peter seems to have known all along. The big mystery is why Josephine would take their son.

The finale’s big reveal

Inside the Irvine home, a tense night reaches its peak as lamplight illuminates a shocking scene. Josephine, hands shaking, has a weapon pointed at people who were just moments before arguing quietly. Marissa and her husband, Peter Irvine, stare in disbelief. Suddenly, Colin rushes forward. A gunshot rings out, and he collapses, a spreading stain of blood appearing on his shirt. “Call an ambulance!” Josephine cries, but it’s too late—Colin dies before help can arrive. “I didn’t mean to hurt anyone,” she wails.

Marissa questions Josephine’s identity, and Josephine reveals her real name. “You’re dead,” Marissa states. “I wished I were,” Josephine replies, her voice hoarse. She clarifies she didn’t come for Milo, but to ask a favor: that Marissa protect him. When Marissa asks from whom, Josephine points to Peter, saying, “You don’t understand what he’s capable of.”

Peter suddenly attacked. The gun went off, and Josephine fell to the ground. Moments later, as she lay there, Peter confessed to Marissa a shocking story: six years earlier, he’d been in a car accident. Marissa had been unconscious, and their baby son died instantly. Amidst the wreckage, he heard a baby crying—Josephine’s child, who had survived. He took that baby, switched it with their deceased son in Josephine’s car seat, and drove home, pretending everything was normal.

“He didn’t belong to us,” Marissa said, her words feeling like a painful blow. “He belonged to her.” Peter attempted to explain, saying he’d believed Josephine was gone and the baby needed care, but his explanations kept changing.

According to Marchant, Peter’s biggest flaw is his constant need to rationalize his behavior, ultimately leading to his ruin. Marchant explains that while Peter’s actions are almost understandable at first, they quickly become extreme. Peter always believes he’s acting to protect and provide for his family, but Marchant argues this is simply a form of manipulation that Peter refuses to recognize.

Megan Gallagher, the show’s creator, always focused on making her characters complex and relatable, even when they made bad decisions. She explains that this was her guiding principle throughout the series, and especially important for the impact of the shocking finale. She wanted the characters to be so well-developed that their actions in the final scene – which took place in the Irvine living room – would feel earned and understandable, even if devastating.

When Marissa finally understands the horrifying truth – that her husband is a dangerous person – she doesn’t react with shouting or panic, but with a chilling sense of helplessness. Actress Melissa Snook, who powerfully portrays this moment, had to show a woman facing an impossible choice: balancing the desires of a husband who ignores all boundaries with the need to protect her young son. Snook explains she focused on what Marissa hoped for the future, both for herself and for her son Milo, even beyond the end of their current struggles. She had to consider what Milo’s life could be like.

What happened to Milo?

Josephine picked up Milo from school and initially hid him in a rental apartment. When police found a picture of Kyle from security cameras at the Chicago Marathon, she moved Milo again, this time to a motel with her father, Rob. While Josephine was out getting a birthday cake for Milo, Peter showed up with a bag full of money, offering it in exchange for Milo’s safe return.

Okay, so the scene is incredibly tense. Rob’s counting cash, completely unsuspecting, and then – bam! – Peter hits him from behind with a lamp, and it’s instantly fatal. It’s brutal and quick. Then, Peter discovers Milo hiding in a closet and, in a really cold move, locks him in the trunk of a car, leaving it at the police station to look like the kidnappers returned him. The timing is crazy because by the time Josephine arrives at the Irvines’ house, Milo is already back home – it’s a lot to process! It all happens so fast, and it’s really cleverly constructed to mislead everyone.

The unresolved questions

When the police arrive at the Irvine home, Detective Alcaras explains that Jenny’s nanny, who they thought was named Carrie Finch, is actually a woman named Josephine. He also reveals that the body found at the motel was Rob. Peter tells a story that isn’t quite true, claiming Josephine’s baby died in the car accident and the gun fired accidentally during a fight, suggesting she was suffering from a mental health crisis. When Detective Alcaras asks Marissa for her opinion, she hesitantly agrees with Peter, saying she believes Josephine was simply unstable.

Marissa listens to a recording from Rob’s phone – the one Josephine intended for her – which reveals what happened the night Rob died. The audio captures Peter visiting Rob at the motel while Milo was hiding. Rob was counting ransom money with his back to Peter, who then grabbed a lamp and struck him. Peter is heard saying, “I saved him. He was mine. He was my son.” This new information makes Marissa realize Peter was the one who put Milo in the trunk and left him at the police station, faking the boy’s discovery to cover up his deception.

Marissa went upstairs, but Peter came right behind her. He admitted he’d killed Rob, saying they would never have been safe. He then asked for Rob’s phone, and after a moment of hesitation, Marissa gave it to him. Peter walked away, leaving Marissa alone on the stairs, where she collapsed and began to cry.

The scene is heartbreaking, as characters finally confront the truth after initially being gripped by fear and disbelief. Gallagher explains she always aimed to create nuanced characters for Peter and Marissa, avoiding simple villainy. She doesn’t write purely evil people because she finds them uninteresting. Instead, she prefers exploring characters who’ve made mistakes, but whose motivations she can understand, even if she doesn’t agree with them. She believes everyone sees themselves as the hero of their own life.

The following morning, Peter’s controlled exterior cracked. He suddenly became angry with Milo over a pair of scissors, roughly grabbing his arm. He yelled, “Don’t you dare run from me! You’re not allowed to leave… you belong to me.” Marissa witnessed this outburst and finally understood how desperately Peter needed to control everything. She told Jenny what she saw, but worried that reporting Peter would mean losing contact with Milo.

Alcaras continues to investigate small details, and a former counselor of Josephine’s remembers instances where she mixed up words, tastes, and colors – experiences that upset her and were never fully understood. This memory stays with Alcaras. Later, a specialist explains synesthesia, a rare inherited condition causing crossed senses. Milo’s unusual use of color in his drawings, previously seen as imaginative, now appears to be a family trait.

At Colin’s wake, surrounded by old bottles, Marissa unexpectedly kisses Peter. She tells him she’s just been missing him, but his reaction is immediate and alarming. He has a severe soy allergy, and Marissa has always been careful to avoid triggering it. Seeing the kiss, panic sets in, and he rushes upstairs, quickly using an EpiPen – though he realizes it’s three years past its expiration date. Marissa asks their friend, Lia, to call 911 and retrieve the emergency medical kit from the car.

Lia is frantically searching for something, with only eight minutes left before help arrives. Peter feels a growing panic as Marissa’s face becomes cold and determined. She quietly confesses she manages his allergies, revealing she intentionally exposed him to soy by kissing him, knowing it would cause a reaction. A flashback shows she’d removed his emergency allergy kit earlier. Peter tragically dies. According to Snook, the actor, it’s a complex moment of both justice and sorrow. It was difficult to portray because her character is simultaneously taking away her son’s father, while wanting her son to remember a good man.

Marissa’s actions aren’t motivated by anger, but by an overwhelming, desperate love—a love that tries to protect by any means necessary, even if it means causing destruction and taking a life. The story, as described by Snook, has the weight of a classic Greek tragedy. Like those tragic heroines, Marissa isn’t seeking revenge; she feels forced into her actions by a heartbreaking realization: the very love that once held her family together is what ultimately led to its downfall. What she does is both a form of punishment and a way to find peace.

The detective who sees everything

At the police station, Alcaras and his partner discussed Peter’s death. His partner thought Marissa might be involved, but Alcaras wasn’t sure they’d ever find out the truth. They then questioned Lia about the food labels at Peter’s wake, wondering if Marissa had checked them for soy. Lia hesitated, remembering Peter accusing her of being responsible for Colin’s death. Ultimately, she decided to protect Marissa, carefully stating that while Marissa isn’t perfect, she’s still just human. Peter is no longer a threat to anyone, now that he’s gone.

Later, when Alcaras visits Marissa, he explains synesthesia – how it runs in families, and how both Josephine and Milo have it. He reveals that, according to his understanding of the car accident six years ago, only Marissa’s husband was conscious and able to act. Alcaras believes Peter was responsible for Rob’s death and hid Milo, and that Marissa didn’t know about it until Josephine showed up with a gun. He acknowledges Marissa felt trapped and made difficult choices because she couldn’t reveal the truth. Despite the case being closed, Alcaras says he’s at peace with how things turned out, even though Marissa won’t face consequences for Peter’s death.

Snook describes Alcaras’s decision to allow Marissa to remain in Milo’s life as an understanding, rather than a condemnation, of her past actions. She explains it’s a tacit agreement where Alcaras acknowledges what Marissa has done, but chooses to prioritize Milo’s well-being. Alcaras believes that despite everything, having some form of consistent parental figure – even Marissa – is best for Milo, given the difficult circumstances.

Gallagher always intended for Alcaras – a character not featured in the book the show is based on – and his final moment to represent the show’s moral center. He explains that for Alcaras, a character who believes he consistently does the right thing, the scene marked a first step into morally ambiguous territory. Gallagher felt Alcaras wouldn’t be able to verbalize what he was thinking, making silence a more powerful choice, allowing the audience to interpret his actions and fill in the missing pieces.

What happens next isn’t so much a solution as a harsh realization – a reminder that justice often hinges on who chooses to ignore wrongdoing. As Gallagher puts it, what’s morally right, legally sound, and what actually happens aren’t always aligned. He’s not suggesting anyone should break the law, but acknowledges that life is frequently more nuanced than the legal system can account for.

A house still standing

Marissa and Milo eventually arrive at Jenny’s house. The boys play with bubbles outside, shimmering in the sunlight, while the women relax on the porch with wine. Though things appear normal, everyday life now feels different and more significant.

In the dramatic climax of All Her Fault, the story finally focuses on the powerful and complex nature of a parent’s love. It shows how this love can be both a source of strength and a willingness to sacrifice everything, capable of building someone up or tearing them down. The ending doesn’t offer easy answers, but rather a realization: the desire to protect can become controlling, justice isn’t always straightforward, and sometimes loving someone means making difficult choices with painful consequences.

Marchant wants the finale to be both thrilling and thought-provoking, particularly about the double standards women face compared to men. Gallagher hopes the show highlights the immense pressure on working mothers, who often feel like they’re leading both their careers and their families. She believes many women her age are feeling incredibly stretched, and while this struggle has been portrayed before, it deserves a deeper exploration in TV and film.

Watching Milo play in the final scene, Marissa finally feels a sense of calm. It wasn’t a return to naiveté – that was lost forever in the wine cellar, along with her former beliefs – but rather an acceptance of her choices. She did what she believed was necessary, and Alcaras understood, allowing her to leave. Most importantly, her son was home, safe and sound. The truth remained hidden, buried with Peter in a deep and lasting deception. Marissa had simply chosen which version of reality would survive, and which would not.

2025-11-07 02:08