Episode 12 of "Law and the City" kicks off with Ju-hyeong and Mun-jeong attending Mr. Park's funeral, an event that draws the entire village, testament to his unwavering dedication and generosity. Back at the office, Chang-won makes a poignant decision to resign and lends his expertise to Yu-deok for a final week. Sang-gi encounters Kim Hyung-min, expressing heartfelt gratitude for the assistance he received through her foundation and requesting her aid in donating funds to Choi Yun-su.
Na Gyeong-min dishes out a stern warning to Ju-hyeong and Mun-jeong, advising them to drop Mr. Park's case in light of his passing, citing its intricacies. Elsewhere, the verdict in Hee-ji's case is announced, with Sun-ja sentenced to three years with five years' probation, sparing her incarceration.
Over dinner, the lawyers share their transformative decisions: Chang-won reveals his resignation, Sang-gi announces his doctoral application and impending departure, while Mun-jeong expresses her intent to interview for an in-house legal position. When left alone, Hee-ji confides in Ju-hyeong her aspiration to become a full-time public defender, to which he cautiously notes the challenges but acknowledges her earnestness. He then teases that he has something important to share.
The narrative shifts to Mun-jeong's interview, where she experiences a realization of her deep fondness for her current role. Ultimately, she declines the offer, choosing instead to participate in a parents' forum where she discovers numerous parents seeking temporary employment – the perfect solution for her maternity leave coverage!
Meanwhile, Hee-ji takes on a new client, Kwon Guk-jin, accused of sexual assault by a new employee who alleges he fondled her thigh beneath a table during a dinner meeting. Shockingly, he admits to the charge but expects Hee-ji to secure his acquittal. Later, Hee-ji's father collects her from work, and their conversation delves into her public defender aspirations, with him also counseling against it.
Elsewhere, Seong Yu-deok burdens Chang-won with an overwhelming workload, while Mun-jeong asserts her right to maternity leave by presenting Na Gyeong-min with a stack of resumes for her temporary replacement. Sang-gi takes Ryu-jin out for dinner, breaking the news of his commitment to the doctoral program and impending resignation, prompting her to insist on a toast to celebrate his journey.
Suddenly, Kim Hyeong-min discovers to her astonishment that her foundation has become the target of a tax audit. This revelation swiftly draws scrutiny upon the law firm as well. It transpires that Lee Dong-su has filed a complaint accusing the foundation of laundering money through the law firm's channels.
Meanwhile, Sang-gi and Ryu-jin find themselves tipsily entwined at a bar. Ryu-jin expresses his regret at having to leave due to her suggestion. While awaiting a bus later, Hee-jiconfides in Ju-hyeong her determination to pursue her aspiration of becoming a public defender. Her experience with the sexual assault case has bolstered her confidence in this endeavor.
The following morning, Sang-gi and Ryu-jin awaken in the same bed, leading to an atmosphere of awkwardness that persists throughout the day. Hee-ji informs her boss of her resignation, thanking her profusely for everything she has learned and experienced. Similarly, Chang-won concludes his last tasks and prepares to move on.
With the support of Hyung-min's foundation, Sang-gi donates his money to fulfill Yun-su's dreams. He reveals to Hyung-min his own aspiration to become a teacher. In return, she confides in him her decision to quit her job as a legal advisor and embark on the path to becoming a practicing lawyer, rather than continuing to content herself with the corporate world and mergers.
Hyung-min hosts lunch with all the partners, informing them of their option to remain merged or revert to their separate firms. That evening, three out of the five lawyers pack up and leave with all their belongings, to which Ju-hyeong and Mun-jeong bid them a fond farewell.
Back in the office, Na Gyeong-min informs Ju-hyeong that Shin Ji-hye is appealing her case against Deus GA, the insurance company responsible for her husband's suicide. He urges Ju-hyeong to represent Deus GA once again, but Ju-hyeong declines and submits his resignation letter. He announces his intention to start his own law firm, driven by his desire to practice law on his own terms. He subsequently meets with Shin Ji-hye to offer her strategic advice on how she can prevail in her case.
After nine long years at the office, Ju-hyeong packs up his belongings and bids the place farewell. A significant time jump later, Mun-jeong returns to the office after giving birth. The law firms have reverted to their original separate entities. Sang-gi has taken up a position as a teaching assistant and is officially in a relationship with Ryu-jin. Chang-won has become a prosecutor, while Hee-ji has realized her dream of becoming a public defender. Ju-hyeong has opened his own law firm and continues to fight for justice in Park Man-su's case. The twelfth episode of "Law and the City" concludes with the five lawyers reuniting for lunch, reminiscing about the journey they have shared.
