Season 1
The show commences with a depiction of a school and its correspondent, Mr. Sakthivel, engaging in conversation with the cleaner, Sagayam, concerning its reopening following the pandemic. Subsequently, we are introduced to Kalaiarasan, also known as Kalai from Namakkal, a young boy observed sitting in front of a house with a knife, and the circumstances surrounding this situation remain undisclosed. He is apprehended by Inspector Nagarajan, who sustains a scar below his left eye due to Kalai. Kalai ultimately finds himself in a juvenile center, where Nagarajan attempts to take his life by utilizing other inmates. Jayakumar, the warden, intervenes and rescues Kalai, sending him to Siragugal Higher Matriculation Secondary School, thereby allowing him an opportunity to restart his life. Mr. Sakthivel advises Kalai to refrain from anger and encourages him to forge friendships of good character. Kalai is employed at Sultan Bhai’s Hotel. Upon Kalai’s entry into the classroom, he is subjected to ragging by Gautham and his associates (Vicky, Gopi, Pandi, Kicha, Vasanth, Shwetha), but Abirami (Abi) steps in to defend him. In a fit of anger, Gautham reports Kalai to Abi’s mother, who is Arvind’s wife. One day, Shwetha orchestrates a scheme by placing her ring in Kalai’s bag, which is witnessed by Abi. Shwetha then lodges a complaint with Puchiappan Sir (Attai Poochi) regarding her missing ring. Although Attai Poochi penalizes Kalai, Abi’s intervention reveals Shwetha’s deceit. Gautham confronts Shwetha about the incident, yet Vicky, Gopi, Pandi, and Vasanth express their support for her. Kicha expresses admiration for Parvathy (Paru). On another occasion, Aadhiseshan, referred to as Psycho Aadhi, harasses Abi in an attempt to win her affection; however, Kalai loses his temper and physically confronts him. Upon discovering this altercation, Rajmohan Sir, Bhairavan Sir, Attai Poochi Sir, Vineeth (Jerry Sir), Malar Miss, and Mr. Sakthivel intervene to halt the conflict. As Attai Poochi Sir prepares to punish Kalai, Abi intervenes by disclosing Aadhi’s misconduct. Following the disturbance, Rajmohan Sir escorts Aadhi to the police station. Sakthivel Sir advises Kalai not to lose his composure. Kalai informs his warden, Jayakumar, regarding his transgressions. Jayakumar confronts Kalai and grants him a second chance. Several days later, the 25th-anniversary celebrations are concluded. Subsequently, Mr. Sakthivel suffers a lorry accident. Before his demise, he instructs his son Gunasekar (Guna Sir) to assume the role of correspondent of Siragugal School. Guna Sir, who had previously struggled with alcoholism, had been estranged from his father due to his drinking habits. He pledges to abstain from alcohol henceforth. Following Mr. Sakthivel's death, Guna Sir takes on the role of correspondent. Months later, Inspector Nagarajan encounters Kalai near Naachiyappan’s Modern School, where Kalai had enacted a koothu drama and received the first prize in an interschool competition; he seizes him and transports him to a secret location near Redhills. Kalai endures brutal torture at the hands of the merciless Inspector Nagarajan. Consequently, Gautham’s Gang (Gautham, Vicky, Gopi, Pandi, Vasanth, and Kicha) and Kalai’s Gang (Chellamuthu, Rajeev, Kuzhandhaivelu, Lavakushan) choose to play cricket near the haunted bungalow where Kalai was previously restrained. Nagarajan summons his mercenaries from Northern India to eliminate Kalai without a trace. However, due to the intervention of Gautham’s Gang and Kalai’s Gang, their plans are thwarted. Enraged, Nagarajan attempts to eliminate them. Just then, Guna Sir and Jerry Sir arrive, overpowering Nagarajan and his henchmen. While the entire group rallies to rescue Kalai, Nagarajan rises and aims his gun at Kalai. Suddenly, a gunshot is heard as Warden Jayakumar arrives, delivering a slap to Nagarajan for his brutality and placing him under arrest. Jayakumar instructs the entire group to ensure Kalai is admitted to the hospital. Under Jerry Sir’s guidance, Kalai begins his recovery. After a few days, Paru is rescued from her forced marriage by the collaboration of Kalai’s and Gautham’s Gangs. They undertake examinations and achieve commendable results. Raghu, who is Sakthivel Sir’s elder son, allies with Siragugal School’s Principal Bhairavan and Modern School’s Correspondent Naachiyappan to take control of Siragugal School.
Season 2
Following the highly anticipated release of the 11th-grade examination results, Gautham's group decided to commemorate the occasion by consuming alcoholic beverages. On their way to the local wine shop, an unanticipated encounter with Pandi's father, a respected bakery owner in the community, instilled a sense of anxiety within the group. To mitigate the risk of potential repercussions, they swiftly opted for beer instead of stronger alcoholic options. Just as they prepared to open a bottle, their childhood friend, Bullet, intervened in an attempt to dissuade them from making a regrettable decision. Unfortunately, Bullet's efforts were compromised as he became intoxicated during the encounter. Seizing the opportunity while Bullet was distracted, Gautham's group discreetly exited the wine shop, only to be detected during a phone conversation with associates of Naachiyappan, a prominent individual whose presence they greatly feared.
With the commencement of the new school term, a fresh cohort of students from Naachiyappan's Modern School—Sangeetha, Madan, Mathangi, Praveen, and Naveen—transferred to Siragugal School, following a detention strategy executed by Naachiyappan. They were soon joined by Sangeetha, who contributed to the evolving dynamics within the school environment. The departure of Jerry Sir created a void that was subsequently filled by Tilottama Miss, the newly appointed educator, taking charge of the students.
Meanwhile, Praveen and Naveen, notorious for their substance abuse facilitated by their dealer, Boodhalingam, crossed a significant line when they disseminated a video that revealed Sangeetha's distressing past, leading to an emotional breakdown for her. In a demonstration of solidarity, Malar Miss, along with Kalai, Abi, Nandhini, Shwetha, and Paru, intervened to support Sangeetha, encouraging her to persist with her education amid the turmoil. During a candid discussion, Sangeetha confided in Kalai about the emotional pain inflicted by Praveen and Naveen, prompting Kalai to take decisive action against the two instigators.
After two years of rigorous training, Santhosh Kumar, affectionately known as Santhosh Sir, returned to oversee the Student President Leadership (SPL) Elections. Gautham, Kalai, and Madan emerged as the primary candidates for the position. However, tensions escalated when Praveen and Naveen vandalized Gautham's campaign poster, falsely attributing the act to Kalai and his associates. In response to the growing conflict, Guna Sir and Amirtha Miss, Raghu's former spouse, urged the candidates to seek reconciliation, underscoring the importance of integrity in leadership. They mandated that the SPL candidates submit a deposit of Rs. 10000 as part of the electoral regulations. While Madan and Gautham promptly complied, Kalai encountered a setback when Praveen and Naveen absconded with his funds to finance their drug purchases. Abi generously offered financial assistance to Kalai, who reluctantly accepted the support after considerable deliberation.
Madan's rise to the SPL position was marred by unethical behaviors, such as selling IPL tickets to younger students. When Malar Miss confronted him alongside Gautham's and Kalai’s group regarding his questionable conduct, Amirtha Miss intervened to de-escalate the situation. One critical day, Kalai discovered Praveen and Naveen smoking on school premises. Outraged by their blatant contravention of school regulations, Kalai confronted them physically, though he ultimately chose to forgive them afterward.
Infuriated by the perceived humiliation, Praveen and Naveen devised a plot against Kalai, enlisting Madan to their cause. Their associates subsequently launched a brutal attack on Gautham and framed Kalai for the incident. Gautham's mother, upon witnessing her son's injuries, demanded accountability from Kalai, who claimed his innocence, asserting that he had no involvement in orchestrating the assault.
Concurrently, Kalai's group, alongside Sangeetha, expressed significant concern for his well-being, apprehensive that the situation was deteriorating. Santhosh Sir, known for his stringent demeanor, imposed severe disciplinary measures on Kalai; however, due to the intervention of Malar Miss and Amirtha Miss, Kalai's expulsion was ultimately averted. Amirtha Miss imposed a strict condition: if Kalai himself were involved in the trouble again, he would resign immediately. Acknowledging the seriousness of the situation, Kalai accepted her stipulations.
Reunited with his group and Sangeetha, Kalai expressed to Gautham's circle his intention to focus on his studies. At the same time, he firmly stated that, had he been present during the previous incident, he would have directly confronted the aggressors. However, Praveen and Naveen, undeterred by Kalai’s resolve, taunted him and warned him to maintain his distance, thereby laying the groundwork for an ongoing conflict.
Shortly after, the students received their deposit back from Guna and began preparing seriously for the upcoming examinations, motivated by the announcement of a tour for those who passed. During this time, Santhosh spotted a cigarette on the school premises, which caused panic in Praveen and Naveen. In an attempt to frame Kalai again, they placed a box of cigarettes in his bag. However, their plan failed when Chella noticed the act and, taking a risky decision, removed the box and placed it in Poochi’s bag instead. Poochi, confused, was left wondering how it ended up there. Upon learning of Praveen and Naveen’s role in the incident, Kalai confronted and warned them.
The examination results were soon announced, and only twelve students—Abi, Kalai, Aadhi, Kuzhandhai, Madan, Mathangi, Shwetha, Sangeetha, Parvathy, Nandhini, Gautham, and Kicha—passed. The others were disheartened, knowing they wouldn’t be able to join the tour. However, Amirtha intervened and suggested that all students be allowed to participate, bringing hope to the rest of the class.
Tragedy struck that same day when a past mistake came back to haunt Gautham and his group: photos from their earlier visit to a bar were published by Nachiappan, who had been waiting for the right moment to tarnish the school’s reputation. The revelation enraged the school authorities. Santhosh punished the boys, and their parents were informed. However, Kalai privately spoke to Guna and convinced him to hear Gautham’s side of the story, believing they would not have engaged in any inappropriate behavior.
The gang then admitted to Guna that they had not consumed any alcohol and had only gone to the bar for fun. Guna, believing in their sincerity, decided to help. With the support of his friends, he reframed the story, claiming that the boys had gone to the bar to distribute awareness flyers to drinkers, urging them to reform. This version of the story went viral, and the school’s reputation was restored.
Despite this, Gautham remained suspicious and did not fully believe Kalai when he claimed to have helped gain Guna’s trust on their behalf.
The much-anticipated tour finally commenced, and everything went smoothly—until the final day, when Sangeetha went missing. After several tense hours, Aadhi was found with her, leading Santhosh to assume that Aadhi had misbehaved initially. However, it was soon revealed that Aadhi had saved her from a group of thugs who had nearly attacked them. The teachers promptly apologized to Aadhi and praised him for his maturity and bravery.
After the tour, the group attended a village festival, dressing up as iconic characters from popular films. As the celebrations concluded, Kalai was nearly spotted by Boodhalingam but managed to escape unnoticed. However, Abi, having followed him, confronted Kalai about his strange behavior every time Boodhalingam was nearby. Emotionally overwhelmed, Kalai finally decided to confide in her about his past and the reason he feared Boodhalingam.
A few years ago, Kalai and his family were living a peaceful and happy life. His elder sister, named Thenmozhi, was known for her righteous nature. In 2022, one day at the factory where she worked, a man named Ravi attempted to misbehave with her and was also involved in supplying drugs to other workers. Ravi was later revealed to be the younger brother of Boodhalingam. Kalai's family filed a complaint against him.
However, Inspector Nagarajan, who was corrupt, sided with the perpetrators. Offended by the family's accusations, he grew angry. Seizing the opportunity, the villains planned a brutal attack. While Kalai had stepped out to buy groceries, Boodhalingam killed Kalai's father Narayanan and mother, and Ravi assaulted Thenmozhi, and they set his house on fire. Kalai returned only to find his entire family dead. Devastated and consumed by grief, he set out to avenge their deaths.
Though initially overpowered, Kalai managed to bounce back. He killed Ravi in front of Boodhalingam and severely injured him before surrendering to the police. This incident was depicted in the first episode of Season 1.
Abi becomes emotional upon hearing his story and assures him that she will support him and never judge him. Meanwhile, Gautham, who was serving as the SPL (School Pupil Leader), learns—along with Guna—that Madhan is closely associated with Naachiappan and has not fulfilled his responsibilities as SPL. Consequently, Gautham is selected for the position, having secured the second-highest number of votes after Madhan.
Life returns to normal, and the school even wins the inter-school sports meet. On the night of the sports day’s closing ceremony, Abi hugs Kalai to congratulate him on setting a new district record in the long jump. Kalai, moved by her gesture, hugs her back. This moment is witnessed by Sangeetha, who breaks down emotionally upon seeing them together. The Next Day, while Sangeetha worries, Aadhi consoles her, unaware of her problems.
Boodhalingam, upon seeing the news of Kalai's extraordinary success in the long jump, was consumed by a furious rage at the mere thought of Kalai still being alive. In his blind anger, he summoned Inspector Nagaraj to his warehouse. When Nagaraj arrived, Boodhalingam unleashed his fury, physically assaulting him and demanding to know Kalai's location. Nagaraj, visibly shaken and trembling with fear, warned Boodhalingam that his name was on the encounter list. He then disclosed his intentions to eliminate Kalai, revealing that he had enlisted the help of henchmen linked to Salem Kadhirvel. The Henchmen try to kill Kalai using a lorry, but he narrowly escapes and reaches the hotel. After showing the Sports certificate to Aanandhagopi Master and Bhir Bhai, they praise him for his achievements. After that, Bhai warns about Boodhalingam's Arrival at the hotel during his absence. On the same evening, while Sangeetha is concerned about Kalai and Abi hugging, the commerce students send her an anonymous love message. When the commotion is heard, the phone accidentally falls. Aadhi picks up the phone, whether intentionally or not, and discovers the love message before turning it off.
The following day, Sangeetha brings her phone to school and expresses her concerns to Guna Sir and Malar Miss, who then inform Santhosh Sir to carry out an unexpected cellphone search. During this search, Santhosh discovers the phone in Aadhi's bag. Oblivious to the situation, Aadhi becomes the target of punishment.
Bhairavan proposes that Guna Sir should expel Aadhi and file an eve-teasing complaint against him. Aadhi insists that he is innocent.
Aadhi feels disheartened when Abi, Kalai, and Sangeetha label him a pervert. Meanwhile, Sangeetha experiences guilt when the actual culprits apologize to her.
Later that night, as Kalai heads to the grocery store for his hotel, he is followed by Boodhalingam's henchmen. After a lengthy pursuit, Kalai's older brother, who works at Bhai's Hotel, escorts him to the hotel. On the same street, Aadhi is out buying groceries for his family, wearing the same T-shirt as Kalai. Mistaking Aadhi for Kalai, Boodhalingam's henchmen break the light and attack Aadhi, stabbing him.
