Classmates movie revolves around Murali (Narain) with his golden voice is the doyen of the college campus. P. Sukumaran (Prithviraj) who is a firebrand student leader with leanings towards the left. Satheesan (Jayasurya) who leads the opposite faction. Vasu (Vijeesh) who is his trusted crony. Pius (Indrajith) who is a rich and spoiled brat and son of Gulf settled parents, is the campus Romeo. Thara Kurup (Kavya Madhavan) who is the daughter of the local MLA and a danseuse who wins numerous awards for the college with her performance. Rasiya (Radhika) who is Murali'lover. Esthappanachan (Jagathy Sreekumar) who is the hostel warden.
It was Murali's dream that these classmates should have a reunion ten years from graduation. But Murali dies under mysterious circumstances. His parents Prof. Iyengar (Balachandra Menon) and Lakshmi Teacher (Shobha Mohan) who both teach at the college decide to fulfill their departed son's dream and bring his classmates together for a reunion.
Sukumaran is now a diamond dealer in Mumbai. Satheesan is now an MLA. Vasu continues to be his sidekick. Pius is now settled in the Gulf. Thara, still unmarried, now runs a dancing school.
The coming together of these classmates is an occasion for the participants to regurgitate the past and go nostalgic.