The first episode of "As You Stood By" unfurls with two friends embarking on a drive, Jo Eun-su at the wheel and Hui-su with bruises adorning her face. The scene then fades into a mundane day, where Hui-su cancels her lunch meeting with Eun-su at the mall, despite already being there. Eun-su, meanwhile, faces her own challenges as Jin So-baek, the guest of the Chinese chairman, steals a diamond watch and hounds him at his workplace, a bustling Chinese market. Despite So-baek's initial claims of borrowing the watch for a promising venture, he returns it that night with a scratch on the strap. Eun-su, with her poise and resilience, convinces him to purchase a new strap and they end up drinking and playing Mahjong. Impressed by her, So-baek attempts to woo her but she refuses.
Back at work, Eun-su runs into Hui-su's husband, who regularly buys jewelry to surprise his wife—a practice Hui-su detests. A VIP customer, Mrs Kang, then begs Eun-su's help as her husband has beaten her up. Before Eun-su can intervene, Mr Kwon arrives and whisks Kang away. As a reward for her discretion, Kwon buys 500 gifts under Eun-su's name, leaving her perplexed and troubled. She takes out her frustration at her evening jiu-jitsu class.
A flashback reveals a young Eun-su hiding in a room with her brother, seemingly traumatized by creaking door openings. It is Mr Jo's birthday and despite being busy, Eun-su and her brother, Eun-hyeok, make an appearance. We witness Mr Jo's abusive behavior towards his wife, only to be calmed by Eun-hyeok.
That night, a single words from Mr. Jo caused an explosion within him, and he violently beat his wife. Eun-hyeok panicked and fled, while Eun-su stepped forward to confront her father. Mrs. Jo begged her to stop, but Mr. Jo's fury only intensified. A flashback revealed Mrs. Jo attempting to jump from a window, and Eun-su narrowly saving her life. The next day, Mr. Jo was ashamed but still upset, and Eun-su tried to report him to the police. However, as Mr. Jo pointed out, the cops don't care about domestic matters, and nothing happened.
A flashback showed teenage Eun-su also being traumatized by people near open windows. While her classmates made fun of her, Hui-su comforted her. Presently, Eun-su missed Hui-su and tried to check on her. Hui-su avoided her, but Eun-su sneaked in and was shocked by the bruises on Hui-su's face. She tried to report it to the police, but as Mr. Jo had predicted, they didn't take it seriously.
Upset by this, Eun-su pushed herself in class, refusing to tap out even when she almost passed out. As a result, she got temporarily banned from the gym. A flashback showed little Eun-su hiding with little Eun-hyeok in the closet while their father beat their mother. When that wasn't enough, she started taking her brother to the park. In another flashback, she tried to kill herself after her mother's suicide attempt, and Hui-su got a scar on her arm while saving her. At Hui-su's wedding, she wasn't ashamed of her scar.
Presently, Eun-su got drunk and So-baek had to come get her. She was embarrassed and left, running into the same Chinese worker who looked like Hui-su's husband. He didn't seem to recognize her, and she was confused. Later, her brother Eun-hyeok learned of her trying to report their father. He apologized for not sharing the burden and decided to move in to protect their mother. That night, Eun-su went to pay So-baek back. He didn't want her money and agreed to a meal. He caught on to her sulking attitude and told her to unleash her crazy if she couldn't move on. Right then, the news reported Kang jumping in front of her husband's car. The CCTV footage showed her outfit which was from the same day as she asked Eun-su for help.
Eun-su's body trembles with a mix of fear and desperation as she frantically attempts to reach out to her mother and Hui-su over the phone. Her mother's voice, reassuring and safe, comes through, but Hui-su's number goes unanswered. Eun-su's anxiety spirals out of control, and So-baek, with a casual disregard for the gravity of the situation, makes a chilling suggestion: that the women should not succumb to despair but instead seek revenge by taking down their abusive husbands. Eun-su initially brushes off the idea, but in a rush of adrenaline, she acts swiftly, stopping Hui-su from carrying out her desperate act of self-harm. Hui-su weeps, her heart aching with the desire to die on her own terms, not at the hands of her oppressive husband. Enraged and determined, Eun-su vows that they will take their revenge by killing Jin-pyo, Hui-su's abusive husband.
