Overlord Ending Explained: The Secret of the Serum

This article contains Overlord spoilers.

Overlord is a beautiful mash-up of genres that will totally catch you off-guard and redefine what can be done with a simple “war film” or “zombie movie.” The unabashed b-movie depicts what initially seems to be a grounded story about American soldiers who land in France to cripple German forces on the eve of World War II’s D-Day. The soldiers’ mission quickly goes awry and the expected Nazi threat unveils itself. However, Overlord takes a big turn when it becomes clear that gruesome Nazi experiments have created something much more dangerous and horrible than ever imagined.

It’s easy to let Overlord‘s addictive, surprising narrative take you over, especially with such captivating monsters, gorgeous cinematography, and bonkers practical effects in play. However, for those that lost track of just what was going on with that secret serum, don’t worry, we’ve got a helpful explanation of the film’s conclusion!

Directed by newcomer Julius Avery and written by Billy Ray and Mark L. Smith, the initial rumors around Overlord placed it as the latest chapter in Cloverfield‘s growing universe, but that speculation turned out to not be the case. Overlord tells a self-contained story, but one that’s in no way any less crazy from the giant monster antics of the Cloverfield movies. It’s almost as if H.P. Lovecraft tried his hand at crafting a Wolfenstein video game.

Five soldiers from the invading American paratrooper squad survive their unfortunate crash landing in Nazi-occupied France, but they quickly begin to lose bodies. Private Boyce (Jovan Adepo) and Corporal Ford (Wyatt Russell) quickly take charge, albeit with contrasting approaches to their predicament. The film also establishes very early on that twisted genetic experiments are being performed by Nazis in a hidden laboratory underneath a local church. The crux of these experiments is not hard science, but rather a mysterious liquid that the Nazis discovered underneath the church. It’s this mysterious fluid that they begin to inject into corpses that has the power to reanimate the dead. Unfortunately, these revived bodies exhibit plenty of zombie-like side effects, super strength, and a whole lot of deformities. Nevertheless, Dr. Wafner, Dr. Schmidt, and the Third Reich plan to use this serum to create an army of warriors that will never die, serve them forever, and conquer the world.

While the film doesn’t answer absolutely everything about this miracle serum, it does explore some interesting hypotheses like what happens if you’re injected and still alive (it drives you insane, for starters). We see what happens when the grievously injured Wafner injects himself with the serum and he still seems to be evolving into whatever his “final form” will be. Ford is able to maintain his grip on reality (if not his good looks) long enough to fight Wafner to a standstill and help detonate the explosives, while Boyce helps finish them—and the serum pit—off in the explosion of the radio tower and the church (not to mention the lab underneath).

Ultimately Boyce decides that this reanimation serum is too powerful and unpredictable to be in anyone’s hands. Not only do the Allied forces decide to not take any of the liquid with them, but Boyce doesn’t even mention its existence to his commanding officers and denies rumors of some secret “Kraut lab.” As far as the American soldiers are concerned, this was just a regular war mission. 

With Boyce and the other survivors transfered to a new unit (as Tibbet quips, you’d think they would get sent home after an ordeal like this), it’s possible that we could see more of this alternate reality version of World War II down the line. After all, this dangerous substance is still under the depths of France, just waiting to be mined. While creating a new batch of undead Nazi soldiers might be a bit too much for a sequel, it’s the kind of supernatural threat that could lead to other WWII-era shenanigans should the Nazis choose to try again, leaving the door open just enough to make Overlord 2 feel like it could happen someday. 

Overlord is in theaters on Friday, Nov. 9.

Daniel Kurland is a published writer, comedian, and critic whose work can be read on Den of Geek, Vulture, Bloody Disgusting, and ScreenRant. Daniel knows that the owls are not what they seem, that Psycho II is better than the original, and he’s always game to discuss Space Dandy. His perma-neurotic thought process can be followed at @DanielKurlansky.