Sam and Dean get acquainted with a new pair of hunters in the upcoming episode 19, titled "The Chitters," of the 11th season of the fantasy horror series "Supernatural."

In a relatively small town in Colorado, human disappearances happen every 27 years in mysterious circumstances. Supernatural hunters Sam and Dean decide to visit the town to look into the mysterious case. When they arrive in Colorado, they meet two hunters who are also on the same mission as the Winchester brothers. Apparently, they have a personal vendetta against these once-in-a-generation monsters.

The promo trailer for "The Chitters" shows a glimpse of the newest case of the puzzling disappearance. A cop in a small town in Colorado tells the Winchester brothers that there are aliens that are attacking people. They later on discover that these alleged "aliens" are called The Chitters. These creatures have human-like form but with bright green eyes. As the supernatural hunters investigate these creatures, they may face a few obstacles along the way.

In other related news, TV Line has confirmed The CW's addition of a new cast member. Elizabeth Blackmore, who currently stars as Valerie in another The CW series "The Vampire Diaries," scored a major role on "Supernatural." She will be introduced in an episode this spring as Lady Toni Bevell and will be explored more in the upcoming season 12. Bevell is described as a visitor with a mysterious background who shares a lot of commonalities with Dean and Sam.

Meanwhile, the previous episode, titled "Hell's Angel" showed Crowly securing The Horn of Joshua to kill Amara. He called the Winchesters to seal back Lucifer in The Cage. However, Sam planned to use Lucifer plus the Horn to execute Amara. Eventually, Lucifer broke her neck, but Rowena successfully helped her recover.

"Supernatural" season 11 airs every Wednesday, 9 p.m., on The CW.