The third episode of "All Her Fault" unfurls with Peter, Brian, and Lia returning home to a house that seems to have lost its tranquility. Marissa informs Peter that the police are still grappling with finding Ana's whereabouts. As soon as Peter steps through the door, Jenny disappears into the shadows, leaving a hush in the air. Marissa delves into the heart of the matter, questioning Ana about the lies and hidden secrets she might be keeping from them.
Just as the conversation reaches a delicate point, Ana knocks on the door, her presence interrupting the tense moment. Before sitting down with Ana, Marissa discreetly texts Alcaras to inform him of her return.
Ana's narrative unfurls, revealing that she and Carrie had once been friends, and Carrie had taken a particular interest in Milo. At first, it seemed innocent, but looking back, Ana realizes that Carrie had been asking too many questions about Milo and his family. She recounts an instance where she, Ana, and Milo met in the city, accompanied by Carrie and a man she never got a good look at due to his hasty departure.
The police arrive, and Ana is led away for questioning. In the interrogation room, Ana shares that Carrie had insisted on meeting them on the day of the city marathon. Peter was participating, and the family had come out to support him. Marissa had asked Ana to join them to help look after Milo. When they all got juice, Ana forgot her phone on the stand and left Milo with Carrie to retrieve it. Upon her return, she saw Carrie arguing with a man in front of Milo, who quickly left without revealing his identity. Carrie later claimed the man was a friend and left shortly after the incident.
Three days have passed since Milo's disappearance, and Marissa and Peter struggle to maintain their composure amidst their anguish. Alcaras and Greco pay a visit to the Irvine household, inquiring about the marathon day events. Marissa begins to blame herself for bringing Ana along to meet clients, but Peter comforts her despite her request for him to stop. Sensing that Marissa is slipping into a dark place, Peter promises them both that they will weather this storm together.
At the police station, Alcaras delves deeper into understanding Milo's life, wondering if the man's hasty departure was because he thought Ana might recognize him.
At Marissa's abode, Colton embarked on a mission to assemble a band of volunteers to canvas the vicinity of Milo's school, with a heartfelt gratitude to Marissa for entrusting him with this task, despite his gambling struggles. A twist of fate, however, casts a shadow over his endeavors as the truth emerges that Colton has embezzled funds from a client's account and is in a precarious position to return them.
Meanwhile, Jenny's meeting with Lee Logan is postponed by an hour, causing her to reach out to her husband for help in picking up their son Jacob from school. He, uncomprehendingly, questions the rationale behind her relentless pursuit of a promotion that seemingly yields no financial reward. Moreover, he shares with her the online backlash she's facing due to resurfaced images from a past party, where she's being falsely accused of employing a nanny to facilitate her social life. Despite these challenges, Jenny manages to captivate Lee's attention and reaffirm her unique stance within the publishing industry.
Elsewhere, Peter receives a chilling call from an individual who knows Milo's favorite dish and claims to have the boy in his clutches. The caller demands that Peter prepare the ransom and keep the conversation hushed. Peter, in a state of urgency, calls his account manager and instructs them to drain his accounts, fabricating a lie to Marissa about going on a drive prior to the canvassing event. He promises to be back in time to assist Marissa with the volunteers, but in reality, he's on a mission to fulfill the ransom demand, driving towards his account manager's office.
Brian persists in offering his assistance during the canvassing, and after a meeting with Lee, Jenny joins the effort. Esther arrives with a bounty of food supplies, much to Marissa's delight. At the station, Alcaras enlists Yuko from the IT team to delve into the marathon footage and uncover the identity of the man Carrie was engaged in a heated exchange with. Unfortunately, Yuko's efforts yield no clear image of the man. The canvassing efforts prove fruitless, but Jenny stands by Marissa, bolstering her belief that Milo is still alive. Peter arrives late, telling Marissa a lie about feeling overwhelmed and unable to stop crying, which Marissa sympathizes with and forgives him for. Brian hides his disappointment from Lia, though his pain is palpable. On her drive home, Jenny receives a call from Alex, Lee's assistant, with good news: Lee has accepted their proposal and wants them to handle his entire catalogue. Meanwhile, Alcaras consoles his wife over the phone as she questions her mothering abilities, especially with their non-verbal son Sam, whose wants and needs they sometimes struggle to understand. During their conversation, he experiences a moment of clarity and returns to Yuko. Together, they obtain footage from a hotel CCTV camera and finally obtain a clear view of the mysterious man Carrie was with during the marathon. Upon arriving home, Jenny finds her husband in a state of frustration, having struggled to care for their son. He makes himself a sandwich and leaves a mess behind, which causes Jenny to silently seethe at his reaction to her good news and her constant cleanup duties. At Marissa's home, Peter and she strive to maintain their composure while Colton calls a colleague and asks her to withdraw funds from Lia's trust fund to replenish Philip's account. Meanwhile, Esther returns home with a picture of the mysterious man from the marathon. Is he her son?
