Embarrassed by the birth of a son, an unwed Kunthi (M.V. Rajamma) instructs her maid to abandon him in the river Ganga. The child is set afloat and is rescued, adopted, and named Karna (Shivaji Ganesan) by Charioteer Adhiratha and his wife, Radha. After maturing he does not want to follow in his foster father's footsteps and wants to be a warrior. Unable to secure the patronage of any Guru due to his parentage, he is assisted by Suryadev and then by Sage Parshuram, and excels in all forms of warfare especially archery. He then befriends Prince Dhuryodhana (Ashokan), will participate in the humiliation of Draupadi - setting the initial grounds of the battle of Kurukshetra - where he will join Dhuryodhana to battle the Pandavas - none other than Kunthi's sons.