“Stranger Things” play cast tease 'the origin of the Upside Down,' Easter eggs galore

The cast and crew of Stranger Things play The First Shadow are still rehearsing for their big debut in London's West End later this year, but they took the time to record a new video to drop fresh story details.

Patrick Vaill, who portrays a young Dr. Martin Brenner in this prequel story, says the play will tell "the origin of Stranger Things" and "the origin of the Upside Down." Producer Sonia Friedman adds, "It's also the origin story of how Henry Creel became Number One."

Given that Henry/One/Vecna will surely be in the fifth and final season of Stranger Things, the play will have tie-ins to series. "There are so many Easter eggs," The First Shadow scribe Kate Trefry says. "It's Easter morning."

Stranger Things: The First Shadow, directed by Stephen Daldry (Billy Elliot), will see the arrival of the Creel family in 1959 Hawkins, Ind. Louis McCartney will be playing troubled psychic wunderkind Henry Creel, while Michael Jibson will play father Victor Creel (played by Robert Englund in the series) and Lauren Ward will play mother Virginia Creel (played by Tyner Rushing in the series).

Stranger Things creators and showrunners Matt and Ross Duffer call Ella Karuna Williams' Patty Newby "a new, really important character." Says Trefry, "The main thrust of the story is Patty and her little budding romance with Henry."

"Everyone's trying to figure out their lives in high school," Williams adds in the video.

Manuel Harlan/Netflix, Steve Dietl/Netflix The origins of Henry Creel/Vecna are told in 'Stranger Things: The First Shadow' stage play

Aside from Vaill's Brenner, the play will also see Oscar Lloyd as young James Hopper, Isabella Pappas as young Joyce Maldonado, and Christopher Buckley as young Bob Newby. Other cast members in known roles include Shane Attwooll as Chief Hopper, Kemi Awoderu as Sue Anderson, Chase Brown as Lonnie Byers, Ammar Duffus as Charles Sinclair, Gilles Geary as Ted Wheeler, Florence Guy as Karen Childress, Max Harwood as Allen Munson, Matthew Pidgeon as Father Newby, Calum Ross as Walter Henderson, and Maisie Norma Seaton as Claudia Henderson.

Jamie Harrison, a co-illusion designer and visual effects artist, says there will be "a lot of monsters, a lot of blood-and-gut effects," and "a lot of vanishes and appearances."

Stranger Things: The First Shadow opens at the Phoenix Theater in London on Dec. 14 with previews kicking off Nov. 17. Watch the full video above.

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