Lucky is an absent-minded junior botanist who is easily distracted by other tasks while working on his current research. His father arranges his marriage with the daughter of Panduranga Rao, a senior botanist. Rao decides to break the alliance after learning about Lucky’s mental condition and warns him not to show up again. On his way to donate blood to his boss, Lucky falls in love with Nandana, a kuchipudi dance teacher, and gets diverted. He creates a positive impression by unknowingly donating blood to one of her students.
In their frequent meetings, Lucky keeps forgetting things (such as going out without his shoes, giving away his motorbike keys to a beggar, etc.), but manages to hide this shortcoming from Nandana by claiming he is a philanthropist. He is unaware of the fact that Nandana is Rao’s daughter, the young woman whom he was supposed to marry before. Rao’s friend’s son Ajay, a police inspector, also falls in love with Nandana, while she is waiting for Lucky’s proposal. When he tries to propose on her birthday, Lucky ends up taking Nandana’s pregnant sister-in-law, who is experiencing labour pains, to a nearby hospital. After the delivery, Nandana proposes to Lucky, and they become a couple.
Nandana informs Lucky that her father has accepted their proposal and wants to meet him. Lucky and Rao meet as strangers when Rao insults Lucky after an incident with a little girl who was about to fall into a pond. Lucky later realises that Nandana is Rao’s daughter and flees. Lucky and Nandana plan to meet later. Lucky makes a friend of his pose as Nandana’s lover, and joins Rao as an apprentice.
When Nandana’s relatives attend the naming ceremony of the new born child, Rao’s nephew assumes Lucky’s friend is her potential lover, and all the others assume Lucky is Nandana’s suitor. Rao’s nephew becomes further confused when Lucky visits a sick Nandana to spend some quality time with her. Days later, Rao wants Lucky to escort Nandana and her relatives to Srisailam. Lucky, driving, misses a turn and reaches the outskirts of Bangalore. He takes them to a nearby temple and explains that it is a very special and historically significant temple.
Ajay, who is confused about the identity of Nandana’s lover (as Lucky and his friend keep changing places depending on who is around at the moment) manages to get a video of Lucky romancing Nandana. When they all arrive back home, Ajay reveals Lucky’s mental condition to Nandana, and they break up. On the day of Nandana’s engagement with Ajay, Rao, who has become aware of the sincerity of Lucky’s love, advises her to choose Lucky over Ajay. When Ajay makes it clear he intends to marry Nandana by force, Rao challenges Lucky to stop it, this time without forgetting.
Rao meets Lucky and reveals that he has been aware of his love for Nandana since the moment she and Lucky met at the hospital, and that, since then, he has been watching to see how Lucky’s amnesia might affect his relationship with Nandana. Lucky visits the temple where the marriage is scheduled to take place but ends up forgetting, instead buying a lemon soda. However, this turns out to be a trick, as he wants to lure Ajay’s henchmen into a false sense of security. He reaches the original marriage venue (actually an aluminium factory) in time with help from Ajay’s henchmen and informally weds Nandana there after a duel with Ajay.
A week later, Rao visits Nandana and Lucky, a married couple, who tell him that Lucky’s condition has been improved post marriage. During their conversations, Rao says that Ajay has been missing for a week and his father is concerned. Lucky remembers that he tied Ajay with a rope at the factory. When he reaches the spot, and Ajay asks why he did not release him, Lucky replies, “Sorry boss, I forgot!”.