123 is a comedy based movie in which, Sreesailam (Nagendra Prasad) is a dumb guy. Badrachalam (Raju Sundaram) is a deaf guy. Tirupati (Prabhu Deva) is a blind man.
These three people are buddies. They behave in such a way that the normal people fail to recognize the disability possessed by them.
Narmada (Jyotika) is a mysterious lady whose background is not known to anybody. She joins in the house that is shared by these three guys. She befriends them and three of them start loving her.
Narmada invites Tirupati to a temple and pushes him on to the stairs from the top. At that time she was not aware that Tirupati was a blind man, as he acts very natural. rest of the story is about who will be get married with Narmada.