Actor Mohanlal who plays a blind man in Priyadarshan's Oppam, says that this is the most challenging one in his entire career. Though the actor has essayed such roles in odha and Guru, his role in Oppam will be the one with a full pledged role as a blind man with a positive vision.Mohanlal's character Jayaraman, despite being blind, is a person who is positive towards life. He doesn't want others to sympathize for him, so he develops some unique skills to stand out.