Elijah (Daniel Gillies), who is Klaus's brother, was killed with the Original vampire-slaying dagger and white ash in the second season finale.
Gillies appeared in flashbacks in a recent episode, but Morgan has now told TV Guide that he would like Elijah to make a proper return.
"I'd love to see someone pull the dagger out of Daniel Gillies," he said. "A huge rivalry, almost like a war between brothers.
"You've got to pick a side - they're going to take each other down. Almost like two corporate giants amassing their armies together. I think that would be exciting."
Robert Ri'chard and Torrey DeVitto are among the stars who have signed up for roles in upcoming episodes of The Vampire Diaries.
The show will return with new episodes on January 5 on The CW.
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