College friends Jenny and Shiva part ways due to a misunderstanding. Although they are in love and realize they cannot live without each other, their egos prevent them from uniting.

Siva (S. J. Surya) is an investigative scribe who shares a live-in relationship with rich and bratty Madhu (Nila). They have hot-headed run-ins and even hotter patch-ups. Things come to a head when Madhu starts a restaurant with a brother of her friend. Nosy and envious Siva cannot take it, and this causes a split between the duo. Fun starts as the fantasy element appears in the form of their apparitional alter egos. Eventually they come together, but there is plenty of over-the-top entertainment aimed at a post-teen youth audience. Anbe Aaruyire features the memories of each other in a human lookalike appearances. These memories remind them of their good times and the inner love for each other, which help in their reunion.

Deva and Shiva (both played by Ajith Kumar) are twins. Deva, the elder, is deaf and mute; but he is a genius, an expert at lip-reading, and the head of a successful advertising company. Shiva loves and trusts his brother. Priya (Simran) wants to marry someone who is an ex-smoker, ex-drunkard, and who got ditched by a girl but is pining for her. Learning this, Shiva, with the help of his friend Vicky (Vivek), invents an old romance between him and Sona (Jyothika), and finds his way into Priya’s heart.
Meanwhile, Deva chances upon Priya and lusts for her. His obsession continues even after his brother gets married to the girl of his dreams, and he devises various means of getting close to Priya and keeping Shiva and her separated.

It is the Tamil remake of ‘Big’. SJ Suryah is a young man with an immature mind. He falls in love with Simran and gets married to her. The troubles that they encounter form the story.