Bangaram (Jagapati Babu) loses his memory in a childhood traumatic incident and is raised by the evil Rudra (Ashish Vidyarthi), who strictly keeps him in a cage in a cellar of his house and raises him into a ruthless fighter who is otherwise quite unkempt and uncivilized, cannot even speak properly, and eats just raw meat. Rudra uses him human bomb when he gets into problems to fight to kill. When Rudra takes off the holy Hindu wedding chain (Mangalsutra) tied to his right hand, off goes Bangaram like a raging bull, an unstoppable machine using the only ultimate weapon he knows: his body. He also uses him to make money by entering him in an underground fight club where the winner is the one who survives.

But, when a turf war ends up in a bloody carnage, Bangaram escapes and is taken in by a kind family consisting of blind piano tuner Vasudev (Kalabhavan Mani) and his teenage stepdaughter Gayathri (Neha Oberoi). Slowly, they teach Bangaram how to be a real person. How to behave and act in the civil society.They also teach him the delineation between good and bad. They even give him a new name Guru. They also allow Bangaram to explore his love of the piano, where a specific tune haunts him, bringing back repressed memories from his long-ago past. In the process, both Guru and Gayathri fall in love. Gayathri is drawn towards Guru, attracted by his innocent and naïve ways of looking at life and things. Just when, Guru thinks he has escaped from his former life, he is pulled back in. But he is no longer the trained dog Rudra thinks he is. Rudra brainwashes Guru that it is his father who has killed his mother. This infuriates Guru and he goes in search of his father to finish him off. When Guru comes to know that Vasudev is his father, he is ready to kill his father. But, Vasudev reveals to Guru, who the real culprit is and why he had killed his mother in a flashback.

In the end, the family reunites and Guru kills Rudra and henchmen in an action-packed climax.