A terrifying Wesen disease returns in the modern-day world on the upcoming episode 14, titled "Lycanthropia," of the fifth season of "Grimm."

According to the official synopsis from Cartermatt, Nick (David Giuntoli) and Hank (Russell Hornsby) encounter a Wesen disease that could be connected with the modern-day werewolf myth. The pair stumbled upon it after an attack in the woods. Adalind (Claire Coffee), on the other hand, gets an offer to be an ally for someone in order to reclaim what she wants the most. While investigating, Eve discovers some unexpected information.

The intense promo trailer for episode 14 shows the team discovering a dead body, most likely caused by an animal attack, in the woods. Monroe theorizes that the attacker is most likely a "Lycanthrope," the other term for the mythological werewolf. His hunch is based on the fact that the victim was attacked under the full moon. Nick and the group have to capture the blood thirsty beast before it kills more innocent people. The clip ends with Monroe, also a wolf-like creature, pointing the weapon toward his own kind.

In other related news, there are recent rumors that the show might end with season 5 only since its ratings are not doing so well. Although there is still no official announcement from NBC regarding "Grimm's" possible season 6 renewal, TV Fanatic recently reported that the ratings of the show's most recent episodes have maintained a stable number. It continues to have 4.2 million viewers with 0.9 rating.

Meanwhile, here is the rundown of the previous episode, titled "Silence of the Slams."

Benitor, owner of Benito's Masks store, is a Wesen named Vibora Dorada. He kills Balam wesens to remove skin from their faces in order to create a luchador mask. He made one for Goyo. He warned him that though the mask can give the wearer powers, it can't be taken off once the person who wears it loses his control. Goyo, however, ignored it and insisted on wearing it. The mask ended up stuck on his face and it was only removed through a Misfortune Ceremony.

"Grimm" season 5 airs every Friday at 9 p.m. on NBC.