'The Darkest Hour' Trailer: Emile Hirsch, Olivia Thirlby Fight for Their Lives (Video)

The Chris Gorak-directed feature is out in theaters Dec. 23.

The Darkest Hour trailer has hit the web. This time, the creatures are unseen.

Starring Emile Hirsch, The Killing's Joel Kinnaman, Max Minghella and Oliva Thirlby, the Chris Gorak-directed and Timur Bekmambetov-produced feature centers on a group of students who struggle to survive after they encounter an alien invasion in Russia.

The plot is nothing new, but based on the trailer, the film looks visually unique. What's more, the unseen aliens -- they're effects are measured only by electricity, energy and when they go in for the kill -- seem a lot scarier than those that have graced the big screen so far this year. "They can see us, but we can't see them," Hirsch's character says in a fit of despair.

The Darkest Hour hits theaters Dec. 23.