Katherine Pierce has gone to Hell — or at least The Vampire Diaries' version of the dark side — and she's not coming back.In the final moments of Thursday's episode, Katherine (Nina Dobrev) made her peace with losing her centuries-long battle to stay alive, but as she put her hands on Bonnie's shoulders, the gateway to the other side, nothing happened. Suddenly, the wind started blowing, and Katherine was sucked into oblivion."It's unlike anything we've seen before," executive producer Caroline Dries tells TVGuide.com. "We've seen characters appear to Bonnie [Kat Graham], the anchor, and go through Bonnie and that's there initiation into the other side. When Katherine died, that didn't happen and [instead] she's ripped out of Bonnie's arms and sucked into wherever by some dark void. We don't say anything religious like Heaven or Hell, but that's the implication — she's going to a dark world."As she series has shown countless times, a character can die and come back to life, but Dries says this isn't their way of keeping Katherine around and they don't intend on delving this darker world."I don't think we'll explore it so much as in the future we'll use something similar happening like that on the other side where it becomes a bit of disarray over there and people get sucked into oblivion," Dries says. "What we wanted when we were writing the Katherine story line this season was to really deliver on her as a character. This show is known for bringing people back to the dead, so death didn't ever feel final; they could hop over from the other side if we feel desperate. So we wanted to say, 'No, she's gone.'"Katherine being the master manipulator, she of course didn't exit without leaving a very deadly parting gift. Poor Elena might be returning to her body, but she's now been injected with the vampire-eating virus that Damon (Ian Somerhalder) has been suffering with. Together the two will have a mighty battle to face in the final chapter of Season 5.