It looks like Stefan (Paul Wesley) is taking drastic measures in the next episode of "The Vampire Diaries" season 8 to save his brother, Damon (Ian Somerhalder), or at least stop him from killing any more innocent people.

In episode 5, "Coming Home Was A Mistake," Stefan decides that they need to "put [Damon] down" as it appears that he has gone to a dark place he cannot come back from.

However, at some point in the trailer for "The Vampire Diaries" season 8 episode 5, Stefan tells Caroline (Candice King) that he will do something that she might not forgive him about. "I might lose him forever," Stefan said.

King has said before that Stefan's efforts to bring Damon back to his normal self will have a negative impact on their relationship, so this could be it.

"Stefan is so attached to protecting and saving Damon. He'll always choose his brother first, and that's going to be a really big thing for this couple," the actress told TV Line.

It looks like the younger Salvatore would do anything to save his brother. Some fans speculate that Stefan will bring back Elena (Nina Dobrev), which would mean that he would have to kill Bonnie (Kat Graham).

The promo for the upcoming episode shows Stefan closing a casket and some say it was that of Elena, who was cursed to be in a deep slumber until Bonnie dies. He was also shown to be holding someone at gunpoint.

Dobrev's return in "The Vampire Diaries" season 8 is yet to be confirmed, though. Executive producer Julie Plec revealed in a recent interview with Digital Spy that she hopes she will return.

"So honestly it becomes a matter of logistics and if we become victim to logistics, then that would be devastating. I'm hoping that's not even going to be an issue," the EP said.

Although the promo suggested that Stefan will be forced to kill his own brother if this is what it will take to stop him, the synopsis for the next episode of "The Vampire Diaries" suggests that he is not ready to give up on Damon just yet.

Meanwhile, the previous episode also teases that Dobrev might come back but as Katherine seeing that the idea of Hell, where she is believed to have been staying all along, has now been brought into play.

"The Vampire Diaries" season 8 episode 5, "Coming Home Was A Mistake," airs Friday, Nov. 18, at 8 p.m. ET on The CW.