Morgan admitted that his character Klaus is in "serious trouble" after being bound to his siblings by a spell, but could find a way to return to dominance yet again.
"He may have found a way [to break the spell]," he told TV Guide. "There's also the matter of the bag containing 12 white oak stakes capable of killing an Original that needs to be taken care of as soon as possible. So he has a two-pronged attack ready.
"We are going to learn a very interesting fact about the Originals' mythology and the bloodlines of vampires. It's not another loophole to how the Originals can't be killed, [but] it's something which has the opposite effect and it raises the threat level right up."
Morgan's co-star Candice Accola claimed recently that fans will see her character Caroline interact with Klaus more as the series goes on.
"I think it's so funny because he's an evil, evil guy and everyone is so excited for them to be together," she said. "But we'll see how the rest of the season plays out, if she is inevitably wooed by him."
The Vampire Diaries airs in the US Thursdays at 8/7c on The CW. It is broadcast in the UK Tuesdays at 9pm on ITV2.
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