Koi Aap Sa is a romantic drama. The movie revolves around two childhood friends Simi (Anita Hassanandani) and Rohan (Aftab Shivdasani). The two go to the same college and Rohan falls for a girl named Preeti (Dipannita Sharma) in their college. Simi helps Rohan to impress Preeti and get the two closer. Simi gets engaged to Vicky (Himanshu Malik). After the engagement party, Ranjit (Gautam Kapoor), Vicky’s friend rapes Simi and she gets pregnant. Ranjit later dies in a car accident. Rohan proposes to Simi for marriage to save her from humiliation. How the circumstances affect the relationship of the best friends forms rest of the story.