Warning: this story contains spoilers for the most recent episode of Invasion (episode 204, “The Tunnel.”) Proceed with caution.

The latest episode of Invasion turned our attention back to Jamila and the gang making their way to France via the tunnel under the English Channel. The last train to go in never came out and the military is blocking all traffic, so the kids decided to ditch the car and walk. What they found inside just might be a game changer, and not in a good way. Those spiky, spidery alien ground troops are no longer a problem, because they have been replaced by a faster, deadlier version!

SciFi Vision wanted to know more about the new threat, so we got together with Invasion’s Visual Effects Supervisor, Erik Henry. He’s one of the best in the business and has worked on some of the most visually striking films in recent memory, including Oscar winners The Abyss, Total Recall, and Batman Returns. In television, he won Emmy Awards for his work on Black Sails and the blockbuster miniseries John Adams. Henry is also busy; in addition to Invasion, he is the senior VFX Supervisor on Tom Clancy’s Jack Ryan and recently served on The Old Man and Westworld. We couldn’t wait to talk to him.

Henry began by explaining how and why the original invaders evolved, and what they have become.

The original spiked creature, he said, “is called the worker alien. The idea is that it was brought here to terraform the planet, and yes, while it is dangerous and kills, it's not until you get into season two that you find yourself face to face with what we'll call the warrior class, where they step it up a notch, and they're a lot scarier.”

The warrior is not a separate species or a different creature; rather, Henry said, the workers are evolving based on the invaders’ needs.

“They start to reach their end of service and they coalesce into a new form that is the warrior class. And in that instance, they've adapted; they become more like a pack of wolves here on planet Earth, because that seems to be a great way to work with our gravity. And hand to hand combat is better for them, because [now] they have appendages that are designed strictly for killing.”

“The idea was that [they could have invaded] any planet; this is just the one they chose. Had it been a water planet, those worker aliens would have changed their shape to work with that. 

"Why do cockroaches exist here? Well, it's because it works well. They've adapted through evolution. We're just saying that evolution with these drones can happen over a shorter period of time.”

Our interview wasn’t all workers and warriors. Henry is excited for audiences to learn more about the crashed ship in the Amazon and the alien entity imprisoned in the lab. He spoke at length about the challenge of creating an amorphous shape that is scary and strange but also has to communicate emotion. “If you had asked me nine months ago,” he confided, “are you going to be able to get an intimate moment between an actress and a thing that is essentially a big blob? I'm not sure. But it worked out.”  Learn how Henry and his team pulled it off in the video below.

Invasion streams exclusively on AppleTV+ with new episodes every Wednesday.