Episode 5 of "In The Mud" kicks off with a nostalgic glimpse into the past, five years earlier, where Cecilia finds herself at the helm of a tumultuous protest. Maria and Zurda, united in their cause, stand as formidable adversaries, urging Cecilia to permit visitors amidst the looming COVID crisis. The dual front of Maria and Zurda challenges Cecilia, demanding that she relent and allow inmate contact with the outside world. Reluctantly, Cecilia concedes, agreeing to a limited use of cell phones within the prison walls. Maria, ever strategic, tasks Zurda with the oversight of these devices, effectively defusing the protest.
The narrative then shifts seamlessly to the contemporary setting, where authorities are probing the mysterious death of a recent inmate in the greenhouse. Cecilia, desperate to steer clear of scrutiny, crafts a narrative of the inmate perishing during an attempted escape.
Elsewhere, Amparo seethes with dissatisfaction, believing Zarda failed in her duty to shield her. Her anger ignites a threat, compelling Zarda to vow retribution against the perpetrator. In confidence to Victoria, Zarda expresses her conviction that Maria's hand lies behind these events.
During lunch, Marina's arrival expands the quintet, but Gladys abruptly exits the table, leaving Soledad, Yael, and Olga puzzled and curious. Marina, sensing the tension, reveals Gladys's irritation towards her. This revelation sows seeds of doubt in Olga's mind towards Marina as well. Meanwhile, Maria is summoned by Cecilia, and rather than acknowledging or denying any involvement in the inmate's demise, she cleverly diverts Cecilia's attention by inquiring about Patricia and her newborn.
Concurrently, Yael breaks the news to Gladys that her daughter will embark on a brief excursion outside the prison walls, accompanied by the governor's wife, a silver lining amidst the ongoing turmoil.
Gladys finds herself pondering the perpetual kindness Cecilia extends towards the pregnant inmates, her curiosity piqued by this peculiar behavior. Meanwhile, Amparo's fury knows no bounds upon discovering Maria's monopolistic control over the prison's meat supplies. Coco introduces Lana to Cleo, who generously vows to assist in reuniting her with her estranged son. In a separate encounter, Marina confides in Lana, unveiling the toxicity of her past relationship with Martin—a possessive individual who, ironically, shared intimate details of their life, including her, with his brother Dario. This revelation stuns Coco and Lana, who promptly promise to stand by Marina's side.
Amparo's gaze falls upon the prison's family unit, where she spots young children playing amidst the adult inmates. Elba enlightens Amparo, explaining that the children leave once they turn five, while their mothers continue serving their sentences. Elsewhere within the prison walls, Marina thrives as a content creator, enjoying privileges such as workout sessions, photographic opportunities, customized meals, and even illicit substances—all arranged by Zurda, who profits handsomely from her endeavors.
From the sidelines, China observes Marina's burgeoning success until one day, Zurda informs Marina of a client's desire for her companionship. Marina declines, but Zurda brooks no refusal, insisting that she must entertain the customer. Gladys visits Zurda's unit to collect her share from Maria, their conversation veering into Amparo. Zurda issues a veiled threat, warning Gladys to steer clear of Amparo. When Marina is compelled to meet the client, she requests Alan's company, a request he curtly denies, leaving her disheartened.
Gladys presents Maria with the money she's collected from various units, while Rocky indulges her in a massage. Maria confides in Gladys, revealing that both her henchmen, Rocky and Cachete, are inmates for having terminated the lives of rapists.
She urges Gladys to brace herself for any potential assault from Zurda and Amparo in the forthcoming days. Maria hands Gladys a weapon from her prized collection, ensuring she is armed for her own protection. That very night, Amparo is haunted by visions of Cuervo, only to awaken to the heartbreaking reality of a miscarriage in her sleep. Cecilia encounters Amparo in the infirmary, offering her solace, yet the latter's heart is shattered, having lost both the love of her life and their unborn child.
The subsequent day, Andrés' wife arrives to spend the day with Brisa, while Marina's mother, Paula, visits her daughter. Paula reveals to Marina that she has squandered all her savings on her boyfriend, leaving Marina astonishment. A cancer screening drive at the prison reveals a possible lump in Gladys' breast, sending her into a tailspin of panic, though she strives to maintain composure. Additionally, Dr. Soriano breaks the news of Vanessa's pregnancy to her, urging her to keep the details confidential.
Marina is devastated upon discovering Alan's marital status, leading her to reluctantly agree to engage in sexual relations with a client. However, her encounter is marred by disappointment as she fails to reach climax, her thoughts drifting back to her intimate moments with Alan. Meanwhile, Yael grows increasingly anxious when Brisa fails to return home that evening. She attempts to visit Cecilia but is turned away. Fortunately, Eugenia arrives with Brisa, prompting Yael to rush her daughter back inside the prison walls.
As the meat delivery arrives, Maria sets out to secure the finest cuts for herself, accompanied by Cachete and Rocky. When Rocky departs to fetch Maria's medication, leaving her alone with Cachete, he invites Amparo and the twins inside. The stage is set for an attack, with Maria becoming the target while Gladys, worried sick about her diagnosis, sobs in the shower. Yael, learning of Gladys' plight, tries to comfort her, leading to an emotional kiss shared between the two women. Amidst this tender moment, the twins brutally murder Maria and gruesomely hang her body on a meat hook.
