In the opening of Episode 3 of "Idol I," Se-na and Chung-jae embark on a city-wide search for Ra-ik. Se-na's efforts eventually bear fruit when she receives a call from the police, instructing her to pick up Ra-ik from the station. Although Chung-jae is reluctant to have the idol under their roof, he reluctantly carries a drunken Ra-ik back to Se-na's apartment.
After tucking him into bed, Chung-jae warns Se-na about getting involved with Ra-ik, who might be the culprit behind the murder. Se-na dismisses his concerns, asserting her commitment to protecting her client to the very end. That night, Se-na checks on Ra-ik and discovers a collection of his stickers plastered on her headboard. Realizing she forgot to remove them earlier, she tries to get rid of them but is interrupted by Ra-ik's cries in his sleep, begging for someone to stay with him. Se-na sits by his bedside and patting him until he falls asleep.
The next morning, Ra-ik wakes up in Se-na's apartment, starts to panic, and tries to leave without saying anything. Meanwhile, Detective Yoo Nam-sik and Byung-kyun visit the forensic expert, who confirms that Woo-seong had no defensive wounds, suggesting that the attacker was someone he knew. Nam-sik is relieved, but the expert adds that the murder was committed with a single, clean swipe of the knife. Byung-kyun questions whether Ra-ik was sober enough to deliver such a precise blow. Nam-sik insists they will review CCTV footage from the night of the murder to gather more evidence.
Outside Goldi Entertainment, fans protest and demand Ra-ik's execution. Se-na meets Ra-ik's former manager, Han-gu, and questions him about the housekeeper, Mrs. Cheongju, who had keys to Ra-ik's apartment. Han-gu claims she was trusted and well-known among fans. Se-na recalls Ra-ik mentioning her and believes him.
Se-na then meets Bo-sang, the CEO of Goldi Entertainment, who she internally curses for being money-minded and heartless toward the Gold Boys. She questions him about terminating Ra-ik's account, but Bo-sang claims it was a shareholder decision. He also reveals that he spoke to Woo-seong the night he died. Jae-hee and Young-bin, the remaining Gold Boys members, arrive during the meeting.
Se-na enquires about their altercation with Ra-ik before his solo concert. Jae-hee defends himself, accusing Se-na of shielding a violent individual. He shows her a secretly recorded video of Ra-ik and Woo-seong arguing, with Ra-ik appearing aggressive. On the way back, Se-na questions whether defending Ra-ik was the right decision. She hears a radio report about Ra-ik's mother, Do Mi-kyung, publicly speaking about her son's involvement in the murder and decides to visit her.
Ra-ik confronts Bo-sang at the agency, accusing him of treating him like a disposable asset and abandoning him. Bo-sang reminds Ra-ik of everything he has done for him, including helping to repay his mother's loans, and complains about cleaning up after Mi-kyung's interview. Meanwhile, Se-na confronts Mi-kyung, who claims Ra-ik was ungrateful. Mi-kyung demands a cut of Se-na's legal fees in exchange for her silence, revealing her greed. Se-na recalls a sad song Ra-ik once wrote and realizes how alone he truly was. She warns Mi-kyung that she will sue and file criminal charges if she continues speaking to the media.
On her way home, Se-na receives a call from Chung-jae saying that Ra-ik is missing. Using a GPS tracker, they try to locate him. Ra-ik, mentally and physically exhausted, is attacked by a group of high school boys who beat him and film it before stealing his shoes. Se-na and Chung-jae run into the boys, recognize the shoes, and Chung-jae forces them to reveal Ra-ik's location. Se-na finds Ra-ik in an alley and calms him down, reminding him of Woo-seong's funeral and asking him to stay strong.
Meanwhile, Hye-joo looks through old photos of herself and Ra-ik and reviews an arranged marriage proposal from Byung-kyun. That night, Byung-kyun speaks with his father, Jong-chul, who mocks him for complicating an easy case. Jong-chul reveals that Se-na was Byung-kyun's childhood classmate and top student. Byung-kyun recalls bullying her when they were younger.
At the police station, Nam-sik's team pores over CCTV footage and discovers Ra-ik leaving a convenience store late at night. Believing this proves Ra-ik's guilt, Nam-sik orders his team to trace his route home.
That night, Ra-ik opens up to Se-na about his dream of becoming a singer after witnessing his mother perform as a cabaret singer. He recalls being scouted by Bo-sang and feeling trapped by constant performances for his mother's sake. He talks about being a troubled teen and meeting Woo-seong, who stayed by his side through everything.
As his fame grew, Ra-ik describes his growing anxiety. When Se-na asks about the argument video, Ra-ik insists it was a routine work-related disagreement. Since his apartment has been seized, Ra-ik decides to stay at Se-na's house until the case ends. Though surprised, she agrees.
The next day, Hye-joo asks Byung-kyun out on a date. During their outing, she questions him about Ra-ik's case. Byung-kyun expresses confidence in winning the case, but when he steps away to take a call from Nam-sik, Hye-joo leaves.
Back at Se-na's house, Ra-ik struggles with attending Woo-seong's funeral. Se-na convinces him to go. At the funeral, Ra-ik mourns his friend. On the way back, Se-na tries to give a statement to the media, but Ra-ik steps in and says he lost his friend and is being blamed for a murder he did not commit. He asks for privacy.
The next day, Se-na and Ra-ik meet Byung-kyun at his office. The prosecutor taunts them, mentions his past with Se-na, and shows Ra-ik CCTV footage of him leaving the convenience store, claiming he arrived home 40 minutes later. Ra-ik refuses to answer questions about the missing time, though Se-na senses he knows the truth. They leave as Nam-sik arrives.
Se-na confronts Ra-ik for lying, but they are interrupted by Hye-joo. The episode ends with Nam-sik telling Byung-kyun that the person Ra-ik met during those 40 minutes was Hye-joo.
