Dostana is a story about two guys, Sameer Acharya (Abhishek Bachchan) who is a doctor and Kunal Chauhan (John Abraham), a photographer. They bumped into each other while looking for an agreement to rent, and confusion headed towards the same bungalow. However, they were both thrown out because the owner wants to re-rent the apartment to girls only, since niece, Neha Melwani (Priyanka Chopra) stays in second apartment alone. Sameer gets the idea (when a US Soldier, who is a gay, tells them about missing his life partner) that if Kunal and he pretend to be gay lovers, then the owner will agree to let them stay. Kunal initially refuses, but agrees out of desperation. Their plan works and they move in. Over a period of time Neha, Kunal, and Sameer become good friends, hanging out together and developing a good relationship as housemates.
One day Neha's boss 'M', short for Murli (Boman Irani) announces that he is resigning from his job as the editor of the magazine called 'Verve' and will also decide who should take his position. In order to impress her editor and get the job, Neha invites 'M' for dinner at her house telling him that she will introduce him to her gay friends. The evening turns out to be a comedy one. But Sameer's mother finds out that her son might be gay and is not pleased. Next day at Neha's office M announces that Abhimanyu Singh (Bobby Deol) will be the new editor. Neha, heartbroken returns home where she is consoled by Sameer's mother. Kunal and Sameer, then help Neha with her on a film project, given to her by Abhimanyu.
While Kunal is out of the film for a few days, Sameer takes Neha to supporting role, and they share a film. Later, at a shop, Sameer tries to tell Neha that he acts her in second scene and that he's straight through a fitting room door, but it turns out Kunal was behind that door and heard everything . Murli becomes angry with Sameer and states that he also marry him. As they try to figure out what to do be gay, Kunal suggests that they should both take Neha out to this great palace called Tajmahal that he knows (Neha's Birthday being the next day). Kunal to catch Sameer the address of the "place", which is actually a dance bar. Meanwhile, he and Neha enjoy eating popcorn and see movie at a cinema. Sameer comes to know of this and furiously punch Kunal in the body. Then, Abhi asked her (Mr Abhi) to take them to where they were going and that they could meet up there and so she did. In a party while the trio are enjoying, Abhi re-enters and sweeps Neha to take her out. Then Kunal and Sameer decide to take him off Neha together. They tell Abhimanyu to do ridiculous things in order to take Neha (like asking him to wax his chest hair and wear ridiculous clothes), but their plan unable to work. They then set their love on Abhimanyu's son Veer. They try to make Veer hate Neha. The next day, Neha comes to know that Abhi is going to propose to her at the basketball stadium they will be not attending . At halftime, Neha goes to see Kunal and Sameer, and asks them what she should do as she had no memory about marriage yet. Both of them ask her marry his brother and reveal that they are not gay and are in not love. Meanwhile Veer tells Abhimanyu of his fears and cries saying that he doesn't want him to marry Neha. As Neha tearfully turns out of Kunal and Sameer, Abhimanyu hugs her and tells her that they can't be together as Veer isn't comfortable with that.
Later, Kunal and Sameer go to the court to collect their resident permits and realize that they miss Neha, so they go to get her at an office that she is attending. They tried explaining to her but she refuses to see and then Abhimanyu walked away. Kunal asks when they are going to get married and Neha tells him that they broke up because Veer Singh wasn't comfortable with her. They both tell them the truth that they were the ones who made Veer Singh hate Neha and Abhimanyu and Neha furiously try to leave the place. But the guys told the securities to stop them and got on to the stage and told the crowd their story and asked them tell Neha to grant forgiveness. The crowd begs them to do stuff like get on the knees and beg to Neha and give a flying kiss to Neha, when one of them asks them to kiss each other . The guys adamantly refuse to do it when Abhimanyu says that since they are very founded gay, it is the only way they can be forgets. Kunal refuses to do it but Sameer convinces him and tries to kiss him, but loses his nerve at the last moment. As Kunal sees Neha and Abhimanyu starting to leave second apartment,Kunal forcibly kisses Sameer. Abhimanyu is amazed, and tells Neha that the guys were really her best friends, as he wouldn't even done that, not even for her. Neha goes to them and they make up. Then Kunal and Sameer got on their knee pain and asked Abhi to marry their best friend Neha, and he said that he will. After two months Neha,Kunal,Sameer,Abhimanyu are sitting on their first apartment balcony and Neha asks them if they ever had any love for each other during the time they were pretending to be gay. They vehemently deny it and Neha walks out of the scene. Sameer and Kunal look at each other and remember their disastrous kiss, and walk out the new apartment.
Thanks to Wikipedia