In Ooty, Kathir is an aspiring entrepreneur who has completed hotel management and wants to own a 5-star hotel. Saravanan is working in a startup abroad and lives with his live-in partner Neetu and Ravi, a music school teacher. Their sister Varshini is expecting, who complains about her workaholic husband Santhosh, and Radhika is Ravi's wife, who tries to get back her romantic relationship with Ravi and tries losing weight but he lost interest long back. Shruthi is their daughter.

Though Saravana is successful, his girlfriend dumps him with "Shining star" Rohan and soon resigns his job and comes back to Ooty. He hides about his job and girlfriend to his parents as they will be heartbroken, but tells the truth to Varshini as she is close to him. Meanwhile, a land where Kathir wants to build his hotel belongs to a Colonel, who will give the land only within his family. Abi is Kathir's close friend, but also has a secret crush on him. At the 25th wedding anniversary of the Colonnel, Kathir and his parents attend, and Kathir devises a plan to marry the Colonel's daughter Diya so that he will get the land. Both the parents accept the alliance and plan to get both Saravana's and Kathir's marriage together. Initially hesistant, Saravana still manages his lie. Ravi is infatuated by Sarah, who runs a music troop and they both have an one-night stand. Later Sarah completely avoids Ravi, and Ravi later gets heartbroken.

Kathir asks Saravanan to pickup Diya from airport as he will be going to celebrate Abi's birthday. Saravanan relucantly agrees and Kathir finds Abi's secret wishes in her diary and makes them come true among the last wish being to kiss her favourite person and they share a kiss. After the kiss, Kathir informs that he is getting the land, and breaks Abi's heart. On the other hand, Saravanan and Diya have a great time and grow closer everyday, due to similar taste. Slowly they fall in love and Saravanan feels guilty about it. Kathir reveals that the school girl, in his childhood, actually proposed him, but rejected as he didn't want to break their friendship. Knowing this, Saravanan avoids Diya. Meanwhile, Abi goes absconding and Kathir misses her and realises he is in love with her. As Kathir goes to meet her, he finds her engaged to Arvind and doesn't propose her.

The family knows about Neetu and Saravanan asks them to find another girl to save the family reputation and also to avoid Diya. Vignesh and Vichu are wedding planners, who make arrangements and also finds a bride for Saravanan, who turns out to be Sarah. Ravi tries many ways to stop the wedding, but everything goes in vain. Radhika grows suspicious about Ravi's behaviour. On the engagement day, Kathir proposes Abi and she takes it as a joke. Kathir promises to get her fall her in love with him within 30 days. Varshini notices Saravanan and Diya and confronts him to which he says Kathir must be happy and promises to get Diya's heart changed within 30 days. Ravi also vows to stop Saravanan and Sarah's marriage within 30 days. all these are heard by the wedding planners and they are shocked. Kathir tries to woo Abi in every possible way but she seems uninterested. He makes some changes in the wedding card without anyone's knowledge.

Meanwhile, Saravanan plans for a surprise on Diya's birthday with her favourite Panipuri and gives credit to Kathir. All the family memebers have a photo shoot and Ravi provokes Sarah's grandmother resulting in breaking Saravanan's marriage. Saravanan wants the family to move on with Kathir's marriage. Kathir tells Varshini about him being in love with Abi. Kathir kidnaps Arvind the next day, and leaves him in some pub where girls misbehave with him, but Abi finds out about Kathir's involvement in this and also asks him why he hadn't cancelled his marriage yet if he loves her truly. She also confronts he always had her as a second plan and never truly loved her and breaks their friendship. Saravanan gets visa to Australia and gets informed by Sarah that Ravi leaked photos of him and Neetu to stop the marriage. Furious, Saravanan chases Ravi and gets to know about Kathir's love and proposes Diya at her home unaware of Kathir's breakup.

Ravi confesses his affair with Sarah and apologises, but Radhika leaves the house with Shruthi. Diya's parents come to discuss about this, but Saravanan denies loving Diya and brings Neetu home as he is confronted by Kathir about his breakup last night. Heartbroken, Diya thinks of going to U.S. Abi finds the wedding card with Kathir's name and believes he always loved her. She accepts his love. All the family members reunite at Shruthi's dance program where she mocks the chief guest- Rohan, which was actually taught by Diya so as to bring peace in Saravanan's heart. Saravanan realises this and goes to stop Diya at the airport. The security stops them and Varshini falsely pretends delivery pain and tells that she wants to talk to the pilot of the plane Diya is flying. It is revealed that the pilot is actually Santhosh. Santhosh and his co-pilot discuss about their family situation. The film ends with the brothers getting happily married with their respective lovers and attend Varshini's baby naming ceremony.