In Buddha Vol. 3, Tezuka focuses on the title character, Devadatta, who will be Buddha's archenemy. Previously, in Volume 2, a rogue warrior named Bandaka resolved to become the king of Kapilavastu, Siddhartha's rightful dominion. Bandaka achieved this title and then decided he wanted a royal heir, no matter what it took. Thus did he bed a noble lady and give birth to Devadatta. However, in their first battle against the almighty Kosalan army, Bandaka was immediately speared and left the auspicious heir an orphan. Devadatta is now a boy, ostracized by his peers because he is the child of a deceased tyrant. Abused and taunted by everyone around him, save the loving mother who believes her son's providence to be a matter of time, Devadatta develops a violent disposition and reactionary behavior against anyone who crosses his path. Finally chased out of his village, he meets a wild monk in the forest who doesn't believe in harming animals. Under his guidance, Devadatta learns the important balance of life and the meaning of patience and perseverance. The monk is no other than Naradatta, who had befriended another stranded boy, Tatta, in Volume One. Yet, from another teacher, the hag Ghagra, Devadatta will learn less uplifting lessons.
Meanwhile, Siddhartha is undergoing the requisite trials any monk must endure in order to reach full ascetic maturity. On his
journey, he meets a mentor, Dhepa, whose fierce commitment to self-mutilation causes Siddhartha to doubt the wisdom of traditional modes of training. The former prince also encounters Assaji, a curiously precocious boy whose selflessness will help the Buddha become Buddha.
