Episode 10 of "Study Group" kicks off with the study group convening to deliberate on Pi Han Ui's impending disciplinary committee hearing. Sun Chul warns them to be vigilant towards Pi Han Ui, suggesting his involvement in Jung-hwa's untimely demise as a desperate bid to evade the committee's scrutiny. The group strategizes to ensure Han-gyeong's safety while facilitating the disciplinary proceedings.
What unfolds for Han-gyeong? As the crucial meeting of the disciplinary committee draws near, she crosses paths with Detective Na, who expresses his apprehension about safeguarding her. The eve before the hearing, an urgent call from the deputy principal entices Han-gyeong back to the school grounds. Cloaked in a veil of contrition, he professes possession of pivotal information pertaining to the school and the Yeonbaek Foundation, compelling her to meet.
Han-gyeong, mindful of the gravity, consults Detective Na beforehand. They devise a plan, planting a recording device discreetly on her coat and preparing her phone to capture the deputy principal's confession. As anticipated, the deputy principal, cowed by the fear of crossing Pi Han Ui's influential father, spills the beans.
However, the narrative takes a dark turn as the room plunges into darkness following his confession, and the deputy principal flees, abandoning Han-gyeong in the inky blackness. Unbeknownst to her, this was all a ruse. Pi Han Ui, accompanied by his steadfast acolyte Min Hwan and others, emerges from the shadows. Min Hwan attempts to seize Han-gyeong's phone but overlooks the recording device nestled in her coat.
Providentially, the device captures Pi Han Ui's own admission of complicity in Jung-hwa's death. He further reveals that Detective Na has been neutralized, dashing Han-gyeong's lingering hopes for rescue. Just as despair begins to engulf her, the study group, her knights in shining armor, bursts in to rescue her from this perilous predicament.
As Ga-min commands Lee-joon to escort Han-gyeong to safety, the rest of the study group braces for battle, scattering across the school to confront Pi Han Ui's gang in various locations. Se-hyeon engages Min Hwan in a strategic and daring confrontation, initially enduring a severe beating with unwavering courage. Sun-chul, despite his shattered arm, stands resolute alongside Ji-woo, their camaraderie shining through the adversity.
Tragically, Lee-joon's encounter with his childhood friend and mentor, Anti, proves to be an emotionally charged struggle, leaving him gravely wounded. The conflict with Anti tears at his heartstrings, for battling one's closest ally and inspiration is a daunting task indeed.
Meanwhile, Ga-min anticipates his long-awaited showdown with Pi Han Ui. Initially, he holds his ground cautiously, hoping to buy precious time for Han-gyeong's escape. Yet, his restraint crumbles when Pi Han Ui reveals his intention to bring the entire gang against their teacher. As Han-gyeong nears the school gate, she is met by a menacing gang of thugs, only to be rescued at the eleventh hour by Hee-won, who emerges as the quintessential savior, rallying Gyu-jin and those Ga-min once saved to her aid.
Inside the building, Ga-min wages an epic struggle against Pi Han Ui, a clash where victory hangs by a thread, as Pi Han Ui proves to be a formidable opponent, nearly matching Ga-min in strength. In a climactic moment, Ga-min sustains a broken leg but prevails, reducing Pi Han Ui to a sorry state and vowing to transform the school's fate.
The aftermath of the tumultuous fray sees the disciplinary committee convene the following day. Pi Han Ui is officially expelled and subsequently arrested by Detective Na in connection with Jung-hwa's murder. As he's led away in handcuffs, Pi Han Ui dares Ga-min to make a difference in the school. Meanwhile, Pi Han Ui's father instructs his lawyer to take charge of the case, though its outcome remains unseen.
Post-arrest, the students unite to dismantle Pi Han Ui's ranking app, bringing a semblance of order back to the school. Fortunately, the deputy principal is also apprehended by the police, clearing the study group's name. Hyun-woo and Ji-woo are joyfully reunited following his release.
Elsewhere, Geon-hyeob secures an internship at YeonBaek Capital, while the study group thrives, cherishing the chance to nurture their dreams under Han-gyeong's wise guidance. However, in a poignant closing scene, she tenders her resignation, leaving a bittersweet aftertaste.
