Adida Melam begins with a little boy being sent to prison for murder. The action cuts to a few years later and we are introduced to Saravanan (Abhay Krishna), a wedding planner, who lives with his mom (Urvashi) and uncle (Mayilsamy). His path crosses with that of Devaki (Abhinaya), who lies to him and uses him to get her friend married off in secret. Saravanan suffers a huge financial loss and Devaki tells him that she will repay his loans if he can stop her wedding to Manohar. He agrees but when Manohar offers him more money, he decides to let the wedding proceed. And on the eve of the wedding...