My fellow audience members look somewhere between tense and excited. We file into a confined space with trepidation, making our way to a bunk bed of our choice. The beds are stacked in three tiers, each hosting an uncomfortably rigid vinyl mattress. It feels as though we’re in a hospital, mental asylum or jail. It’s warm, and my skin sticks to the vinyl.

Once in our bunks, headphones go on as confused whispers between guests float through the room. Anxiety builds.

This is Coma, the third installment of UK immersive-theatre company Darkfield's popular shipping-container productions, which is coming to Fringe World next year.

As with their previous shows Séance and Flight (which are also showing at Fringe World 2021), Coma takes wary punters inside a pitch-black container, where darkness leads the mind to confusion, and even persuasion.

Before the lights go out, we’re instructed to consume something sitting at the side of our beds. Knowing not to take consumables from strangers, we all search around the room for confirmation that everyone will do it. We all agree.

The lights go out and the next half-hour makes clever use of the other senses – sound, smell and taste – to stretch the mind and allow the group to fall into a dream state together. This is where reality begins to bend, as sounds and spoken word come through the headphones, smells drift by, and the air moves (or does it?).

“The darkness is like another texture that surrounds you,” co-creator David Rosenberg tells me, a few days earlier. “You become fairly susceptible to suggestion from the sounds, and there’s this doubt as to what’s happening around you.”

“We try to blur that moment where the audience doesn’t know what’s real and what isn’t,” adds co-creator Glen Neath.

Are the whispers and chatter coming from your headphones or the container? Is there really someone inside the container, pacing between the bunks? Can you smell them? Did your friend cough? What is real and what is not? These are the questions whizzing through my brain as I navigate the total darkness before me.

Once the time is up, our dazed and confused bodies wobble out of the doors, grasping for words to share with our fellow guests. Nobody says a word to the punters eagerly awaiting entry. It’s as though there’s a collective decision that what happens inside, stays inside.

Neath and Rosenberg say this collective consciousness is an important element of their shows, and a result of the situational darkness especially. “The audience brings a lot to the shows,” Neath says. “Everybody has a different response because it’s such an extreme scenario to be in the complete dark.”

“When the lights go out, the space has gone as well,” Neath continues. “So you then try to recreate the space as a group. And once you’ve imagined the space, then what else can you imagine in the space?”

The concept of allowing the mind to wander and build its own narrative is a large part of the inspiration for Neath and Rosenberg, too. “We can really see how the imagination works in the audience and how they can create their own environment,” Rosenberg says.

“There’s so much interest in anything that’s immersive these days ... but I think there’s something paradoxical about immersion. In fact, books are probably one of the most immersive art forms because it’s all about your imagination ... it’s not about being given everything all around you. For us, taking away vision for the audience, putting them into darkness and actually limiting some of their sensory input is the thing that creates a gap for the audience to fill in for themselves.”

Coma is showing at the Woodside Pleasure Garden from January 15 to February 14, 2021. Tickets go on sale November 17.