Teach You a Lesson Episode 10 Recap (Finale)

Gyu-cheol baits Hwa-jin

At the Ministry of Education, the team looks for footage of the Jinwon High School rooftop where Lee Chi-ho fell. No camera covers the roof, and the only angle, from a building next door, is too blurry to show much. Zoomed in, it leaves room for someone behind Chi-ho who could have pushed him. A protest sign accuses the Educational Rights Protection Bureau (ERPB) of driving students to their deaths.

Inspector Na Hwa-jin seeks out Cho Gyu-cheol and asks why he came back to this school and reported the bullying so fast. He knows Gyu-cheol wants the bureau gone, he says, and he bets the pills are the reason. Heart Pills were sold as Butterfly Pills two years ago, and the newest batch is called Diamond. Gyu-cheol points out that Hwa-jin has no proof, or the police would be there. He calls Hwa-jin as meddlesome as Choi Ga-yun was and wonders aloud whether he will end up like her.

In a flashback, Ga-yun tracks down Gyu-cheol, who refuses to go to school. She treats his injuries and vows to stick to him like a fly trap. The next day she finds him with a group of smokers, says she is his teacher and leads him away. Gyu-cheol later tells an associate what Ms. Choi has taught him: a school is full of customers, restocked with hundreds of new buyers every year. Soon he turns up in uniform, and a delighted Ga-yun offers to buy him a meal.

Back in the present, Gyu-cheol tells Hwa-jin that the two of them would be married by now if Ga-yun had looked the other way. He warns that the bureau already stands accused of excessive punishment and that a blow would look like personal revenge. Hwa-jin hits him anyway. Gyu-cheol breaks into a stream of apologies, begging the inspector not to hit him any more.

The bureau is suspended

A television report links Chi-ho's suicide attempt to the assault on Gyu-cheol. A politician, by context Hwang Gi-tae, says the bureau targeted Gyu-cheol from the start out of personal revenge. He calls Chi-ho its victim and vows to have it dismantled. Polls show half the public agrees.

At Jinwon High, students jeer the bureau's arrival and ask how it can investigate Chi-ho's case fairly when it hurt him. An announcement follows: all ERPB duties, the inspectors' work included, are suspended until the inquiry into the Jinwon High student is closed. Deputy Director Bong Geun-dae finds himself locked out of his account.

With the bureau gone, Gyu-cheol's ring starts moving its product. The plan is to seed each school's dealers with samples and push hard once a school passes 100 customers. Students make ideal runners, the ring reasons, because minors draw no suspicion and are easily replaced. One runner is recruited to deliver resold sneakers, and the boxes reach Soyeon Girls' High School.

In a biology class, a girl credits pills for her weight loss, hands them around and texts for more samples. A teacher leaves because a student has crashed the motorcycle he bought with delivery money, and his classmates plan to take over his route. Teachers say students are skipping class and admit they felt safer when the bureau was around.

Online, requests for ADHD medication and beauty pills pile up. The ring counts 17 schools in Seoul with about 100 orders each and blasts its offer over Telegram. Jang Seong-gu is handed a package someone saved for him. He leaves Hwa-jin a message asking to meet at the convenience store across from school, but when Hwa-jin arrives, Seong-gu tells him by phone that something urgent called him home. In the ring, someone calls Seong-gu a good kid and says it is a shame.

The plan behind the punch

A member of the team reveals that Hwa-jin set up the whole operation in secret. When a colleague asks whether the punch was part of it, the answer is that Gyu-cheol had to move before they could get evidence, and that meant the bureau had to vanish, as Gyu-cheol wanted. Hwa-jin says he will take full responsibility once it is over, and the others offer to share it. Minister Choi Gang-seok cuts them off: he will carry the blame himself, and they are to stick to the original plan.

Without hard evidence, police backup is unlikely, so Inspector Im Han-rim says the three of them will manage around the clock. She is asked why she thinks it is only three. In a video message, Gang-seok warns teachers of a new drug spreading through Seoul's middle and high schools and asks them to work with the bureau once more. Messages pour in. A teacher offers to help, and teachers bring in pills collected at their own schools.

Outside schools, students pass the pills around as diet vitamins. In staged shakedowns run by kids who used to know the trade, students hand the pills over as vitamin C. With the samples in hand, the team places an order through Telegram. The bureau then announces that teachers found a new substitute for the recently banned Heart Pill, and that its supply leads to the main dealer, Cho Gyu-cheol of Jinwon High. The suspension is lifted and the inspectors return to work.

Han-rim walks into a trap

The inspectors move in on the ring. A colleague tells Inspector Im that a container will not open. Someone shouts not to open it and not to inhale, and Han-rim is exposed to the drug. The dealers gloat that the bureau fell for their trap and ask whether she got a taste. As they run, Han-rim announces that she can fly, calls out her final descent and jumps after them, landing hard. She tells Hwa-jin to keep going, and Geun-dae promises to look after her and sends him ahead.

Still high, Han-rim tells the dealers she can be an angel or a devil, and chooses devil. One of them pulls a real knife, and they gang up on her as Geun-dae shouts at them to leave her alone. The dealers are beaten and the knife taken away, but Han-rim turns dizzy.

Ga-yun's last words

Hwa-jin catches up with Gyu-cheol, and a flashback returns to the day Ga-yun finds Gyu-cheol's drugs. She has not called the police because she wanted to give him another chance, she says, but he must turn himself in. Gyu-cheol asks whether she has told anyone and refuses. As a minor from a broken home with no motive, he says, a manslaughter charge would cost him two years at most, and he could come back and sell again. He tells her he has loved her all along and that she will not be getting married now. Her last words are "Gyu-cheol, you can't do that." Gyu-cheol kills her.

In the present, Gyu-cheol pretends to give up, saying he is no match for an inspector, and Hwa-jin offers to hit him just once. Gyu-cheol warns that if Hwa-jin moves, another innocent person may die at this school, and Seong-gu is held hostage. He stabs Hwa-jin. He will spare Seong-gu, he says, when Hwa-jin goes to see his beloved fiancée, and asks him to pass on an apology. Gyu-cheol talks of fleeing abroad, since there are schools everywhere. Han-rim arrives, names herself as an ERPB inspector and joins the fight.

Hwa-jin tells Gyu-cheol he has thrown away another chance. Every citizen, he says, has a right to an education suited to their abilities and to happiness, and anyone who stands in the way must be taught a lesson. Gyu-cheol begs for his life and another chance. Hwa-jin answers that a chance is earned by wanting it, the words Ga-yun once said to Gyu-cheol. Gyu-cheol says the two were made for each other, repeats her last words, rages that nobody cares about him and demands that Hwa-jin kill him. Hwa-jin beats him but stops, saying he cannot do that, and tells him to start over, calling it the last chance Ga-yun will ever give him.

When Gyu-cheol asks who they think they are, the reply is "We're adults, punk. That's all." He is put in a police car and charged under the ERPB Act and the Controlled Substances Act, with attempted murder and with several violent offenses. He is expelled from Jinwon High and barred from ever returning. Gang-seok learns that Hwa-jin was stabbed and needs a few stitches. He charges at the car, shouting about his son-in-law, until the others hold him back.

The bureau is back at work

At the Ministry of Education, Gang-seok addresses the nation. True education, he says, builds character as well as knowledge and skills, and integrity matters more than good universities or jobs. Korea's system has strayed and is broken, though most teachers still do their work well. He pledges that the bureau will stay until schools stop being places of fear.

At a memorial to the late Choi Ga-yun, Gang-seok tells his daughter it is good that so many people remember her. Offered a tissue, he insists he never cries. Hwa-jin says Ga-yun told him otherwise: Gang-seok wept for a month after a stray cat he looked after was adopted. Gang-seok then demands the Jinwon High report, the others joke about workplace harassment, and he raises his fists.

On a walk, Han-rim and Geun-dae bicker over who held whose hand near a rock, while the others note that the two like each other without knowing it. A flashback returns to the raid, where a drugged Han-rim begs Geun-dae to help her sober up and he kisses her.

Later, a scouted athlete lines up his teammates and reminds them they are headed to Hanguk University only because of him. When they have no money, he makes them pay another way. Geun-dae steps in, introduces himself by his full title and says the ERPB is going to teach them a lesson. A scuffle follows until the rest of the team arrives, and an inspector tells the athletes that the revived bureau puts no limits on its methods.

Gi-tae, helped up by aides, warns that he will be back and that his accuser will be the first he brings down. Gang-seok says Gi-tae knew the truth when Gyu-cheol handed him the recording and should have stopped it then. People like him, he adds, turn students into monsters. Gi-tae shoots back that Gang-seok must have skeletons too. Gang-seok admits he is not a good person either and punches him, and onlookers gasp.

See every episode in the Teach You a Lesson episode guide.