Chakkaramuthu movie is about Aravindakshan (Dileep) who is a sought-after tailor, specialising in blouses, working in a shop owned by Kumaran (Cochin Haneefa). Despite his evident mental difficulty, Aravindakshan is shown as worldly-wise, with his own way of dealing with things.
He loves Anitha ( Kavyamadhavan) deeply in his heart while she feels pity of him. In fact, he is known as her Black Cat security. One day, he tries to kiss her when his friend Santosh (Kalabhavan Nawas) instigates him. She is shocked but later uses the incident to cover up her love with Jeevan (Jishnu) from her strict mother, who wants her to marry doctor Rajiv (Sarath).
Anita's uncle (Sai Kumar) a police officer and mom fix her marriage on learning about her affair. She however elopes with Jeevan and goes to Bangalore with the help of Aravindakshan but soon realizes that Jeevan is a cheat. The rest of the film is on what happens to Anitha and Aravindakshan’s deep love for her.