10 TV Shows Where The Hero Became A Villain

1. Willow Rosenberg - Buffy The Vampire Slayer

Buffy the Vampire Slayer had a number of its heroic figures cross over to the dark side: most famously, there was the split between Angel and Angelus, while Faith too broke bad, and even Buffy herself flirted with morally questionable actions. But none were such a major shift from where they started to the villain they became than Willow Rosenberg.

Willow was every bit the sweet, geeky best friend type. She was kind, loyal, and helpful to anyone who'd ask, and so it was for a few years. Things started to change as she dabbled more and more in magic, which she used to exert some sense of control over people, but it was something she struggled with. We saw her dealing with that, and rooted for her throughout. She was Willow! She's the nicest person around.

The real shift, then, came in Season 6. It started when she erased some of Tara's memories, which was the first real moment fans had to seriously question her actions. When Warren, attempting to kill Buffy, accidentally shoots and murders Tara, Willow's already on her way to villainy, but this cements it. The magic already building within Willow took a hold, alongside a desperate thirst for revenge over this unimaginable pain, and Willow utilised dark magic to pay Warren back and then some, resulting in the gruesome scene where she turns him inside out.

That wasn't the end of it though. Dark Willow became too powerful, and what started as a grief-fuelled revenge trip turned into an almost unstoppable witch intent on destroying the world, with the good Willow increasingly eroded away by her use of dark magic until there was only a faint trace of her left. Thankfully, that was enough for Xander to get through to her, but at the height of her powers even Buffy was unable to stop her.