Sam Winchester is becoming increasing aware that something is not quite right as Supernatural heads into its midseason finale, "Holy Terror."

Possessed by Ezekiel, the younger Winchester brother is slowly healing from his trial trauma from the inside out. However, Sam (Jared Padalecki) is beginning to notice his life seems to have more and more strange time gaps. In the new sneak peek below, Dean (Jensen Ackles) has a 50-mile conversation with Zeke that leaves Sammy completely bewildered.

'Supernatural': Is Sam Still Ready To Die? Jared Padalecki's Character May Have 'Sacrificial' Feelings VIDEO

In the meantime, the angel war is heating up and there's a new player on the scene - a fellow named Malachi. The previously unknown power is creating an army out of his fellow fallen soldiers, and he doesn't take too kindly to those who refuse to join, according to Spoiler TV.

Although the Winchester brothers will get to team up with one of their few allies, the now human Castiel (Misha Collins), Malachi won't be the only problem on their plate.

'Supernatural': Metatron Returns in 'Holy Terror' PHOTOS; Finds Heaven 'A Little Lonely' VIDEO

Metatron (Curtis Armstrong) is making a visit from his heavenly perch, and it looks like he is going to have a chat with Sammy. This may end badly considering there is someone else inside the hunter who may have a thing or two to discuss with the man who dropped him from his home.

With several storylines coming to a head, "Holy Terror" promises to be a can't-miss episode - a sentiment the series' actors are quick to agree with.

'Supernatural': 'Awesome' Midseason Cliffhanger, Metatron Returns PHOTOS, Malachi Prepares for War in 'Holy Terror' VIDEO

"We're filming our mid-season cliffhanger episode right now," Padalecki tweeted on Oct. 17. "And, I gotta admit, it's AWESOME!!"

Supernatural airs Tuesdays at 9 p.m. on the CW.