A scream rippled through the Phoenix Theatre in Londons West End on a Saturday night in late November.

The cast were only minutes into their latest runthrough, so the reaction came as a shock.

Was she screaming from fear or excitement?

Stranger Things: The First Shadow

Henry Creel (Louis McCartney) and Dr. Martin Brenner (Patrick Vaill) in ‘Stranger Things: The First Shadow’.Manuel Harlan

And they did it and it’s absolutely insane.

“It touches on several themes and ideas that we will continue to explore in the show.”

“Netflix was very excited as soon as Stephen Daldry brought up the idea,” the Duffers remark.

Stranger Things: The First Shadow

Henry Creel (Louis McCartney) enters the Black Void in ‘Stranger Things: The First Shadow’.Manuel Harlan

Once we had a great script, it was off to the races."

1, and Vecna twist (that they’re all the same character).

Everybody was like, Oh s!

Stranger Things: The First Shadow

Isabella Pappas as Joyce Maldonado, Christopher Buckley as Bob Newby, and Oscar Lloyd as James Hopper Jr. in ‘Stranger Things: The First Shadow’.Manuel Harlan

Thats literally never happened to me before and it will never happen again.

What we did was, Can you write a couple of episodes as if this were the series?

We will then venture to find the theater language to do that.

Act I ofThe First Shadow, he notes, is more like a pilot episode.

Act II is the second, and so on.

Why is this happening here?

Why is Hawkins Lab there?

Why is Brenner there?

It could be any town, which is to say every town has a shadow.

Many of the actors didn’t know what they were getting into initially.

“You had to shred any old version of the scripts,” Pappas adds.

Hes really a pioneer, Trefrey points out of this moment in particular.

Hes the first to go into that and understand that.

At the same time, the play will also be expanding upon the mythology ofStranger Thingsin various ways.

At the end of the day, the characters are what carry the show."

Theres so much crazy s that happens in the first five minutes of the show.

The same is true of the stage play.

We had a little issue at the last show.

I think it’s at its best when it’s about suggestion, Martin explains of the horror elements.

It’s like, as soon as you see a giant spider… Im using this as an anecdote because there is no giant spider in the show.