Elena's return in "The Vampire Diaries" Season 8 finale may lie on one person-Kai Parker. Kai's return in the series could mean he wakes Elena, which in turn, prevents Bonnie from having to sacrifice herself.

The CW has released photos for the Feb. 17 episode of "The Vampire Diaries" Season 8, which reveal the return of Kai. The villain Kai, portrayed by Chris Wood, first appeared in Season 6. He is responsible for putting Elena in an induced coma.

Now fans are probably questioning his purpose for coming back. Naturally, viewers would speculate that Kai is there to undo his spell on Elena (Nina Dobrev). If this is true, then he would be doing Bonnie a favor. After all, Kai linked Elena's chances of waking up to Bonnie. The only way that Elena wakes up, is if Bonnie sacrifices herself, which means she has to die.

Now with Kai back, then perhaps both Bonnie (Kat Graham) and Elena survive. Perhaps Kai is there to set things right. However, it remains unknown whether Kai suddenly turns good and decides to help Elena. The synopsis for the Feb. 17 episode, however, hints he remains a villain.

The synopsis for the episode from TV Line labeled Kai as an old enemy. Damon (Ian Somerhalder) and Alaric (Matthew Davis) reunites with him after they retrieved a weapon that could kill Cade.

Entertainment Weekly shared photos of Kai's appearance on the Feb. 17 episode of "The Vampire Diaries" Season 8. The images hint that this weapon Damon and Alaric retrieve is a dagger. Kai is wielding the weapon in the photos.

Meanwhile, Nina Dobrev is set to reprise her character in "The Vampire Diaries" Season 8 finale. However, fans still do not know whether she returns as Elena Gilbert or Katherine Price. Still, Kai's presence teases Elena returns and not Katherine.