The 'Teen Wolf' season five midseason finale is expected to bring on a handful of revelations for viewers and Scott’s pack members alike.

While fans found out about Theo’s association with the Dread Doctors in the start of the action-packed season, it seems that his trustworthiness will finally be ascertained before the midseason finale.

“With both lives and friendships on the verge of being destroyed, Scott and his pack are going to face their greatest enemy yet,” the synopsis for the ‘Teen Wolf’ season five summer finale stated.

In a sneak-peek video for episode 10, Theo (Cody Christian) confronts Lydia (Holland Roden), and reveals that he is not really an ally.

In the footage, Lydia is shown having a sort of forewarning. “You know what’s coming, don’t you?” Theo asks.

“Someone’s going to die here,” Lydia responds. Although she does not mention any names, Theo seems to know who it is.

“Right, I can’t let you tell anyone,” he answers back.

As Lydia expresses confusion, she feels the need to warn people that someone is going to die. “I want you, Lydia. I want all of you,” Theo opens up.

“What are you talking about?” Lydia asks.

“Don’t worry,” Theo says. “I’ll give you some time to think about it.” He goes on to punch Lydia in the face and knocks her out.

Theo could be referring to the fact that he wants Scott’s (Tyler Posey) pack. As pointed out in previous promo videos, Theo revealed that he wants Scott’s powerful friends, and that he does not feel the need to be associated with Scott himself.

"I never lied why I came to Beacon Hills," Theo told Stiles (Dylan O'Brien) in the previous clips. "I'm here for a pack. Unfortunately, it doesn't include Scott."

Aside from Theo’s true commitment, fans will also learn about the real nature of Parrish (Ryan Kelley) after being teased for over a year.

Series creator Jeff Davis told Zap2it promised fans that they will "exactly" learn about Parrish's supernatural identity in the first 10 episodes of season five.

Upon learning his character’s identity, Kelley said it was not a big surprise for him as Parrish's real nature is something that the actor has already heard of before.

"I'm a big nerd, so there are a lot of things I'd been speculating about, which I don't think people would have known," Kelley explained. "I love everything supernatural, Greek mythology, all that. I had a pretty good handful of things I thought Parrish was, so it didn't shock me."

‘Teen Wolf’ season five, episode 10, the midseason finale, is set to air this Monday at 10 p.m. EDT on MTV.