'The Vampire Diaries' season 8 spoilers: Nina Dobrev's appearance confirmed? Sybil, Damon and Enzo forming alliance?

The final season of "The Vampire Diaries" is promising to be action-packed and intense with the supposed entry of a female villain and the return of fan-favorite Nina Dobrev.

In the season 7 finale of the show, a voice that sounded very much like Elena Gilbert's (Dobrev) lured Damon (Ian Somerhalder) and Enzo (Michael Malarkey) into the vault. However, the voice could actually be Sybil's (Nathalia Kelley), season 8's yet-to-be-confirmed villain.

Sybil's character has been described as an immortal with the capability to use influence and power to control others. Being the enigmatic creature that she is, she just might pull Damon and Enzo further into the dark side. It looks like Sybil gets the high from manipulating people, although it cannot be confirmed yet whether the mysterious character is a friend, a foe or both.

According to reports, Damon, Sybil, and Enzo time in the vault could have them scheming and secretly working on a mission that will probably be revealed when "The Vampire Diaries" season 8 starts. TV Guide notes that fans will find out soon enough why there seems to be an alliance between the three dark characters, and that apparently, their collaboration will be for the benefit of the series finale.

Meanwhile, Hollywood Life reports that Dobrev's Internet Movie Database (IMDB) page has recently been updated to include her appearance in the eighth and final season of "The Vampire Diaries." The publication notes that Dobrev will be reprising her role as Elena on episode 16 of season 8.

The official Twitter page was quick to take a screenshot of the page and posted it for Dobrev's fans to feast on.

An official confirmation is yet to be made by The CW and Julie Plec, showrunner of the series. Nevertheless, it looks like it's all systems go for Dobrev's return to the show that made her a household name.

It also looks like Somerhalder's tantrums during the San Diego Comic-Con that had him explicitly expressing his annoyance over his ex-girlfriend's return to the series have gone unnoticed by Plec.

"The Vampire Diaries" season 8 will air on at Oct. 21 at 8 p.m. on The CW.