| Director | S. U. Arun Kumar |
|---|---|
| Budget | ₹55 crore |
| Box office | ₹66 crore |
On the night of the local temple festival in Madurai, tensions escalate between SP Arunagiri and former mobster boss "Periyavar" Ravi, leading to the former deciding to kill the latter and his son Kannan in a staged encounter. Ravi goes to his former enforcer, Kaali, for help. Kaali, now a provision store owner, leads a blissful life with his wife, Kalaivaani "Kalai", and their two children, Janani and Dilip. He does not want to resort to violence again but eventually decides to help Ravi as he begs him and assures him that he will not get caught.
Kaali and Venkat, his former friend and Ravi's nephew, get hold of landmines from Ravi's old house after Kaali decides to use traditional weapons rather than modern ones so that even if they succeed, the deed would not be traced back to them. Kaali sets up a few landmines and connects them with a string so that Arunagiri's vehicle would run over the string and explode. However, in the process of doing so, Venkat suffers a seizure, leading to him falling with Kaali in tow, who barely manages to grab him before Venkat is about to hit the mines and trigger them. They ultimately fail to kill Arunagiri, and Kaali reports the same back to Ravi. Kannan comes into the picture and intervenes, threatening to kill Kaali and his family, who are at the temple festival.
A flashback reveals that on the day of Kaali and Kalai's marriage eight years ago, Kaali's best friend Dilip was killed by a police inspector through sheer police brutality after Dilip had called him in an informal tone. Since then, then-DSP Arunagiri was also present when Dilip was taken into custody in public, and the inspector is also the son-in-law of an influential MLA. Periyavar (then only Ravi) and Kannan, who hope to secure a big mining contract in the region, are told about Dilip by Arunagiri and decide to use the information to blackmail the politician into giving them the contract, all the while pretending to be ignorant of Dilip's death in front of Kaali. Eventually, Arunagiri tells Kaali and Kalai about Dilip's fate, and a devastated Kaali decides to kill the politician. With Venkat and a couple of other men, they attack the inspector's house when he is with his family. However, Kaali refuses to kill him and instead decides to surrender to Arunagiri. At the police station, when the politician rudely speaks of Dilip, Kaali brandishes a hidden locally handmade gun and shoots him, while also killing the inspector. Ravi and Kannan then make an appearance and promise Arunagiri that they will ensure his suspension is brief as long as he keeps quiet about them knowing of Dilip's death beforehand, and Kaali is left untouched. Arunagiri is subsequently suspended for a year for preventing the murder of the MLA in his office, and that incident has kept his career stagnant in powerless positions. Arunagiri had to beg and bribe politicians to be promoted to SP and then wait patiently to return to Madurai.
In the present, Kaali discloses Kannan's location to Arunagiri as Kaali was worried about his family's safety. Kaali catches up with Arunagiri, telling the former to get Kannan to disclose Ravi's whereabouts. When Kaali goes to talk to him, a phone call from Kannan's mother tells him that there is a black sheep amongst them. In the process, believing the three men that are with him are the traitors, he shoots them dead, whilst not finding out that it is actually Kaali. Eventually, Ravi's men come to rescue Kannan, and a shootout ensues between Kannan and Arunagiri's force. They are all shot and killed, except for a gravely injured Arunagiri and another inspector. Kaali finds them, and Arunagiri tells him that the only way he can come out of the other side is by somehow keeping him alive and letting him do his job. However, while escaping, his car is hit by Kannan's. As they go to Ravi with Kaali and Arunagiri, he learns that Kaali was the black sheep. The latter fights back by hacking Kannan's arm off and killing him and his men afterwards, whilst Arunagiri assures Kaali's safety.
Kaali reunites with Kalai and tells her he killed Kannan, much to her dismay. They find that Venkat was eavesdropping on them, leading to a chase where Kaali contemplates killing him but ultimately decides to let him go. However, the latter suffers from another seizure, prompting Kaali to go back to his house to get water for him. As he is about to leave to tend to Venkat, Ravi arrives with his family, and they soon learn of Kaali's involvement in Kannan's death, prompting an intense confrontation at his house. Ravi kills an injured Arunagiri for playing a role in Kannan's death when he promises him not to do anything if they decide to kill Kaali and his family. However, Kaali fights back and eventually kills Ravi and his men using the landmines. He leaves afterwards, telling Ravi's grieving wife that he had to protect his family at all costs. He and his family board a bus and leave town for good. Kaali smiles at the kid who boards the bus with her parents. The kid smiles back at Kaali, recognizing him as the one who helped her mother when she fainted while returning from Ravi's home.