Fans of "The Maze Runner," the best-selling YA book by James Dashner about to hit theaters as a major blockbuster movie, know that it's all about the Grievers -- bulbous, evil, bio-mechanical monsters that terrorize Thomas ("Teen Wolf" star Dylan O'Brien) and co. as they try to navigate a massive, unexplainable Maze.

And we at MTV News are certainly fans of "The Maze Runner," which is why we're thrilled to debut this exclusive clip, "Hide," that offers up a spine-tingling sneak peek at a Griever... Or at least, part of one.

In the clip we see Thomas, Teresa (Kaya Scodelario), and the rest of the terrified Gladers running (and hiding) for their lives as the Grievers begin a horrifying attack. Grab the popcorn!

"The Maze Runner" hits theaters on Friday, September 19. And be sure to catch Dylan O'Brien on the "Teen Wolf" finale this Monday (September 8)!