Vennila is a Tamil daily soap which airs on Sun TV. It used to air at 2 PM daily, except Sundays. Later a new serial came on the channel which pushed it back by one hour. Thangavelu is the writer of the daily soap. Raj Prabhu, S.Sekkilar and K.Shanmugam, have provided the screenplay for the serial. Vennila is a story about a girl from a small village who faces all kinds of problems. Being in a small town, she would continuously be harassed by people. Nobody would respect her there.
Life had become difficult for Valli to continue living there. Later she finds out that her uncles want her to get married. Valli doesn't want to get married but she is going to be forced to marry by her uncles. It seems that there is a rich man in the nearby town who will pay them money if he gets to marry Valli. After getting to know about this arrangement, Valli decides to run away from her town and never return to the place again. She knows that people over here will not help her as everybody would take the side of her uncles.
Once she reaches the big city, she is lost and she doesn't know what she is going to do. Valli soon learns that life in the city is worse than the life in her hometown. She is facing all kinds of problems from which she doesn't know how to escape. Valli finds out that she has a twin sister named Vennila. She is blind and is married to a person called Anand. Valli is encouraged by Vennila; she takes up her identity and tackles all the problems in the city with the help of a lady called Rajeswari.
The manner in which Valli solves all her problems is the core of the story. Vennila’s husband, Anand, never attended school due to the evil plans of his uncle, Shankar. Shankar used to torture him, and he even made him afraid of his elder brother Prakash. Vennila is pregnant and is admitted to one of the hospitals. Prakash and Shankar plan an accident to kill Anand. Anand somehow escapes and is admitted to the hospital. Anand is currently in a coma. After he comes out, Valli takes it upon himself to teach Anand English which he never had the chance to learn.