The Walking Dead: Daryl Dixon filmed in a haunted set: "The crew swear they saw ghosts"

The season 2 finale of The Walking Dead: Daryl Dixon had a little of everything, from Daryl singing to bioluminescent zombies in the eerie depths of the Channel Tunnel. It concluded The Book of Carol in an unexpected way, seeing both Daryl (Norman Reedus) and Carol (Melissa McBride) head to England. But the journey is far from smooth, with the duo encountering a wholly new type of zombie.

After scurrying away from the post-apocalyptic French revolution, both Daryl and Carol found themselves heading to the relative sanctuary of England. While they don't know what awaits them there, it's sure to be a safer place than France, where the country was at war.

However, in order to cross the border, they must venture through the Eurostar tunnel, an old railway line fallen to disrepair after the apocalypse. Naturally, the walkers that lurk in the darkness have changed with their environment. Now they're bioluminescent messes, unlike anything we've seen before. And moreover, the air within the tunnel is unclean, resulting in toxic fumes that cause our heroes to hallucinate vividly.

While the cast and crew didn't film in the Eurostar tunnel itself — which is still very much in use today — they did film in a nearby tunnel which is significant in its own way. "Right up on the Normandy coast, very close to the entrance to Eurostar, the train that goes to England. It was a tunnel, if I’m right, I was told was built by the Nazis, during the second World War for the defenses of Normandy coast," director Daniel Percival revealed to TVInsider.

""There’s a story, I don’t know how true it is, that during an area bombing mission, Hitler’s train was on a visit to the Normandy beaches and British Intelligence had found out about this and they went to bomb the train and they went and hid in that tunnel. So, Hitler was supposed to have been in that tunnel.""

The process of filming was a huge challenge. Of course, old tunnel infrastructure doesn't exactly lend itself to huge productions. "We were in that tunnel for days and days and days, the riggers and the electricians were having to lay kilometers of cabling because it’s a huge tunnel. And it was the right size and concrete lined in the way that Eurostar is, so we felt if it decayed, that this is kind of what it would look like," Percival added.

Despite there not being any real zombies, Percival reveals that some of the crew left with ghost stories of their own. "[The crew] swear they saw ghosts in there. It was not a pleasant place to work."

"It was dark when you turned up for work, dark when you left, and dark inside. But it had an atmosphere to it that fueled the filming as well. It took 20 minutes walking just to get to the set. It was a huge and insane undertaking, but we did it."

Kudos to the team for pulling it off. They could've quite easily filmed in a studio, but they filmed everything as authentically as possible.

The Walking Dead: Daryl Dixon season 2, The Book of Carol, has now concluded. All six episodes are now streaming on AMC.

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