10 MORE Worst Betrayals In Horror Movie History

In Neil Marshall's directorial debut, British soldier Cooper is on a routine training exercise in the Scottish Highlands when he and his squad are besieged by a pack of werewolves. After rescuing their wounded captain, Ryan, Cooper's group decide to hole up in a farmhouse owned by a zoologist named Megan.

Although the werewolves are vicious, the troops look like they can manage, since they're well-trained and heavily armed.

But if only it were that simple. Ryan eventually admits the whole operation was a lie. His superiors sent him to capture a live werewolf and so, used Cooper's squad as bait to lure the creatures out. Ryan reveals he's been bitten by one of the beasts, forcing his squad to turn against him after changes into a werewolf.

While Cooper is dealing with Ryan, he learns there's another wolf in the fold. It turns out Megan is a werewolf too and she only led the group to her home so her pack could eat them.

Due to Ryan's antagonist nature, his betrayal is pretty predictable. But Megan's true intentions are genuinely unexpected, since she behaved like she had Cooper's best interests at heart.