Who is the villain of JoJo? One per part, and blood that rules nothing

The short answer is that JoJo's Bizarre Adventure doesn't have one villain; it has one per part. In Part 1, Phantom Blood, it's Dio Brando, who returns as DIO in Part 3, Stardust Crusaders, surrounded by servants like Vanilla Ice. In Part 2, Battle Tendency, it's Kars, leader of the Pillar Men. In Part 4, Diamond is Unbreakable, it's the office-worker killer Yoshikage Kira. In Part 5, Golden Wind, it's Diavolo, the hidden boss of Passione, who sends hitmen like the surgeon Cioccolata. In Part 6, Stone Ocean, it's the priest Enrico Pucci. And in Part 7, Steel Ball Run, whose anime Netflix premiered on March 19, 2026, it's President Funny Valentine, with Diego Brando as Johnny Joestar's rival. If you need a single name, it's DIO: his shadow reaches all the way to Part 6, where Pucci acts as his disciple. Parts 8 and 9, JoJolion and The JOJOLands, have antagonists of their own that the archive hasn't filed yet. (Spoilers for the first seven parts from here on.)

Since Hirohiko Araki started it in 1987, the series has followed two bloodlines across more than a century, the Joestars and the Brandos: it's a family tree with superpowers. Criminology once tried to read crime in the family trees of real people, and it went so badly that it's now taught as a warning. The guide to JoJo's villains analyzes each of them on their own; this post takes the question that ties them together: whether evil in this saga is inherited.

// The theoryThe Jukes, the Kallikaks and bad blood

In 1877, Richard Dugdale published The Jukes, which traced a New York family with prisoners, paupers and sick people in every generation. Dugdale gave great weight to environment, but his readers turned the book into proof that degeneracy ran in the blood. In 1912, the psychologist Henry Goddard went further with The Kallikak Family: Martin Kallikak, a soldier in the Revolutionary War, supposedly fathered a son with a barmaid whom Goddard labeled “feeble-minded,” and later raised a family with a Quaker woman. One branch, according to the book, produced misery and crime; the other, model citizens. Goddard coined the surname from two Greek words, kalos (good) and kakos (bad). One man, two bloodlines: the theory of criminal heredity in its purest form.

That's where those studies led. Eugenics used them to justify forced sterilizations in the United States and Europe, and Goddard's book was cited in the case that became Buck v. Bell. Today the theory is discredited. Family studies never separated what is inherited from what is shared at home: poverty, hunger, a marked surname. Walter Lippmann already faulted Goddard for failing to show biological rather than social heredity, and his field staff diagnosed “feeble-mindedness” at a glance. Stephen Jay Gould also charged that some photographs looked retouched, a charge that has itself been disputed. Today's genetics finds, at most, moderate heritability for some temperament traits, which matters only depending on the environment. Nothing is left of “crime in the blood.”

Read Dio Brando’s full case file · Evolutionary criminology →

// The caseOne body, four sons and no destiny

JoJo's has its own Kallikak case, and it settles it the opposite way from Goddard. At the end of Part 1, DIO takes over Jonathan Joestar's body, and with it he fathers sons by different women: Joestars and Brandos at once. One is Giorno Giovanna, the protagonist of Golden Wind, who carries the Joestar star birthmark on his shoulder. Three others, Ungalo, Rikiel and Donatello Versus, appear in Stone Ocean working for Pucci. Same blood, opposite paths, and the story tells us what separates them. Giorno grew up with a mother who left him alone and a stepfather who beat him, until as a boy he protected a wounded gangster who, grateful, made sure no one touched him again. Ungalo arrives in Florida hooked on drugs; Versus was locked up as a boy in juvenile detention for a theft he hadn't committed, and came out broken and bitter. Pucci gives them what no one else had: a purpose.

The rest of the saga keeps making the point. DIO's true heirs aren't his sons but the people who choose him: Vanilla Ice cuts off his own head to give him his blood, and Pucci, who doesn't share a drop of it, spends an entire part carrying out his plan. In Diamond is Unbreakable, what passes from father to son isn't a gene either: Kira's father, trapped as a ghost in a photograph, uses an arrow to create Stand users who will protect his son. What he passes down is a cover-up. Diavolo does the reverse and tries to kill his daughter, Trish. And when Steel Ball Run resets the universe and creates another Dio, Diego Brando, Araki doesn't give him only the blood: he gives him the poverty again, the mother dead of exhaustion, the humiliation.

// The crackNot being the blood doesn't make him a victim

The opposite temptation is just as comfortable: if evil doesn't come from the blood, it must come from the neighborhood or the cell, and then no one is responsible. Not so. Versus's life explains his grudge and Diego's poverty explains his hunger to rise, but neither was forced to do what he did. Giorno carried the same blood and his own abuse, and chose another path. Explaining is not excusing, whether the explanation is biological or social.

Fiction can afford a star on the shoulder that marks the good guys, because Araki controls every variable. Real history already tried reading families that way, and the result was Buck v. Bell. Anyone looking to JoJo's for proof that evil is inherited is repeating Goddard's mistake; anyone who watches what the saga does with DIO's sons will see it says the opposite. Every one of its villains is in the JoJo archive.