Poongavanthamma (Padmini) is a lonely old woman who lives in a town named Malligaipanthal. She is frequently irritated by the neighbourhood, the nearby school boys ringing the bell frequently for fun, sneezing while she is going to temple, keeping loud noise in the speaker etc. A girl (Nadhiya) comes to her home one day and rings the calling bell. Mistaken for the irritating boys, Poongavanathamma comes to thrash them but is surprised on seeing a young girl who introduces herself as Sundari her grand daughter. Poongavanthamma does not invite her inside and tries to shut the door but Sundari manages to get inside the home. Sundari explains how she knows about her grandmother and how she came here etc. but Poongavanathamma does not reciprocate to anything.
Sundari being a mischivious girl starts her prank with the neighbour David (S. V. Sekhar) a young man by scaring him with the demon's face mask while he is working out in his terrace. She befriends the boys who irritates her grandmother and does all sorts of fun, pranks and becomes loving girl in her area. Sundari finds that her grandma likes Yellow color very much and tries to impress her with that. But Poongavanthamma gets angry and throws her out of her home at a night. But she again takes her back and explains why she has behaved like that.
Poongavanthamma being a single mother has got all sorts of affection to her daughter. She permitted her daughter to marry a man of her choice on a condition that the groom must stay and live with them forever. But the groom did not keep the promise and he took away her daughter from him. After the death of her daughter she pleaded to get back the child from her son-in-law to which he refused. She also had an unsuccessful legal attempt to get the custody of her grand daughter as she is too old to take care of a child. Since 17 years neither Sundari nor her father visited her home. This made her frustrated and angry as her waiting for 17 years to hear the calling bell rung by her grand daughter did not happen. Sundari promises her grand mother that she will never leave her alone no matter whoever calls her. From then on Poongavanthamma and Sundari become intimate with each other. Sundari also finds how affection is her grand mother towards her at many stages. Poongavanthamma removes the much troubling calling bell as her desire got fulfilled by Sundari's arrival.
Sundari wanted a Yellow rose pot to have it in her garden and finds out that David is having one. She visits his house to request him and pranks him that the cooling glass which she wears makes the wearing person to see only the body of the person and not their clothes. David is shocked by that and runs away from her view. David wants to revenge her by stealing the glass and look her without her clothes as she did to him. He manages to steal the cooling glass but finds that Sundari did a prank on him. This further angers him and waits for a time for him to come. Sundari invites David for the Deepavali festival combined with her birthday party. David presents her a set of crackers which delights her. But Sundari gets injured when bursting his crackers and David gets satisfied that his plan worked. Sundari understands about David and tells him that all her pranks were meant only to make people happy and not to hurt them and apologizes him if she had hurt him in any way and treats her injury as her birthday gift by David.
David's friend Alex visits his home and recognizes Sundari who is the friend of his sister. He immediately rushes to inform her father about her whereabouts. When David asks for reason he informs him that Sundari is counting her last days. Sundari met with an accident a few days ago. She was treated and discharged from the hospital; however, she was diagnosed with some brain disorder which requires a major operation for survival which does not guarantee to save her life. Sundari does not want to lose her life without enjoying it and she cannot tolerate the hard feelings of her family and hence she came out uninformed. David feels very bad for behaving with Sundari in that rude manner and he apologizes her for his acts.
Sundari's father Sundaram (Jaishankar) visits Poongavanthamma's house to pick up his daughter but Poongavanthamma neither allowed him inside nor to explain why he had come. Sundaram seeks the help of the town's Church priest and headmaster of the town's school to allow him to take his daughter with him. Sundari gets promises from everyone including her father that her grand mother should not know about her condition. Poongavanthamma and Sundari get into a quarrel one night and Sundari is compelled to tell the truth about her by herself. Poongavanthamma visits the church that night itself and expresses that she has no objection to take Sundari for operation and she would make her sleep as Sundari would not go with them while she is awake. As said so she makes her sleep and Sundari is transported in an ambulance for the operation. All others except David leave the place and David sees Poongavanthamma fixing the calling bell again hoping that calling bell would again rung by her grand daughter Sundari.
Sign up and get access to some cool features. Create watchlists, check in at movies, rate them or even write whole reviews! You can also share literally everything on Moviebuff with your friends, enemies, frenemies, family, babysitter or pets. Is that enough incentive for you?