Oru Kal Oru Kannadi abbreviated as OKOK is a 2012 Tamil romantic comedy film written and directed by M. Rajesh. It stars producer Udhayanidhi Stalin, in his acting debut, Hansika Motwani and Santhanam, whilst featuring Harris Jayaraj's music and Balasubramaniem's cinematography. The film was named after a song from the film Siva Manasula Sakthi (2009). Releasing on 13 April 2012, it opened to highly positive reviews and became a blockbuster. It was eventually released in Telugu as OK OK on 31 August 2012.
One morning in his house, Saravanan receives his ex-girlfriend Meera's wedding invitation. He and his friend Parthasarathy aka Partha leave for Pondicherry to attend the wedding via car. En route, Saravanan recollects his past: He was a easy-going youth working in a film theatre with Partha. He lives with his parents; his father, Varadharajan, who is educated and works as a college professor and his mother, Shenbagam, who is uneducated and is trying to pass an exam, just to get her college degree and her husband's love, since Varadharajan had stopped talking with her the day after their marriage when he found out that Shenbagam is uneducated. One day in traffic, he sees Meera, a girl training to be an air hostess and falls for her on site. He stalks her to a cloth shop and also to her Air Hostess class. He saw her house and he and Partha go to her house, as Meera calls them. There, Meera threatens Saravanan by showing her father's photo, who is a Deputy Commissioner of Police (DCP), Mahendra Kumar. But still, Saravanan stalks her and asks her to love him. Meera takes him to Mahendra Kumar's office and he asks Saravanan to stop following Meera. Meera tells Saravanan that she has some qualifications required by her lover like shaving regularly, dressing well, breaking his friendship with Partha, coming on time, etc. Saravanan tells this to Partha and Partha asks him if he or Meera is best for him. Saravanan tells him Meera is more important to him than Partha, causing a break between Saravanan's and Partha's friendship.
Later, Saravanan joins Partha's broken love and asks him to rejoin his love. Partha agrees and then they go to Mumbai, following Meera in a flight. There, Meera alas tells him that she loves Saravanan. Meanwhile, Varadharajan later realizes his mistake of mistreating Shenbagam and reconciles with her after Saravanan scoffs him for his behaviour when she turns up late at night which had worried him. After some months, Meera calls Saravanan once, but he does not pick up the phone and tells Partha that Meera is not his real love and it is all nothing, but a "project". But, he really said that for fun. But, Partha had accidentally switched on the phone while Saravanan told him all this. Meera, mistaking him for intentionally misusing her, comes there and breaks their love. At the present, Saravanan's parents arrange to betroth him and Meera by going to the temple, while in Pondicherry, both Saravanan and Partha end up drunk (Saravanan truly drinks for the first time, shocking Partha since Saravanan often inebriated earlier by just sniffing the booze bottle as a running gag in the film) and tell a small story to the guests, in a comical way describing the broken love of Saravanan and Meera. The guests empathize with them and just as the marriage is about to happen, Rajini Murugan, a local don, comes there with a pregnant girl and his girlfriend and reveals that Meera's groom has a girlfriend, who is pregnant by him and that the girl Rajini Murugan is with, is that girl. The groom admits to his mistake and reunites with his old girlfriend. Saravanan and Partha walk off the marriage hall, just then Meera comes and hugs Saravanan, hence reuniting with him.