Devadoothan movie tells the story of Vishal Krishnamoorthy (Mohanlal) who is a musician who has attained international fame on account of his symphony 'Rhythm of Love'.And from the point where Vishal attains international repute, the director takes us back on a journey into his past, when certain unseen forces make him solve certain mysteries surrounding Angelina Ignatious (Jayaprabha), the lady who runs the college from where Vishal was once expelled. Angelina was once in love with Maheshwar (Vineeth) who is a blind musician and who disappeared after saying that he would return with his mother's consent for their marriage. But he never came back and Angelina went on waiting for him.And it is in this context that Vishal, who had made a rather unsuccessful musical album or two, is brought in to do a musical play for the students of the college.
Two students, especially Sneha and Manoj are doing the lead roles in the play, which rather coincidentally, tells the story of Angelina and Maheshwar. Sneha, who is an admirer of Vishal's music, becomes intimate with him. In the meantime, Vishal and Sneha are taken into a weird world of spirits, weird occurrences etc and in the end everything is resolved, with Vishal finding a clue to Maheshwar's disappearance.