After Bonnie became the anchor to the Other Side, Kol comes to her offering a deal. He knows of a powerful but secretive coven of witches who could resurrect him and also restore her lost magic. He’s been associated with them for centuries and they owe him several favors, and only he knows where to find them, but as a ghost he can’t contact them without Bonnie’s help. Bonnie becomes resolved to regain her magic, especially if it means she can use it to protect herself from the agonies of being the anchor. Together they track down the coven, and Kol is successfully resurrected. Restoring Bonnie’s powers is a more complicated, painful affair and could potentially destroy her if her resolve wavers. Kol remains by her side to talk her through it.