Stephen King teases It: Welcome to Derry's "terrifying" first episode, as he gives the horror spin-off his public seal of approval

It: Welcome to Derry's first episode is "terrifying", according to Stephen King – and fortunately for horror fans, he seems to be just a big a fan of the rest of the season too.

He took to Threads on October 7 to describe the series as "amazing". While he didn't say any more than that, it's still quite the endorsement from the author who penned the book on which the show is based back in 1986.

Acting as a prequel to Andy Muschietti's It and It: Chapter Two, It: Welcome to Derry was largely inspired by the interludes in King's original novel, in which Losers Club member Mike Hanlon recounts his investigation into the titular town's dark history. From the mysterious disappearance of the Roanoke settlers and a devastating factory explosion to the burning of the beloved club The Black Spot, Mike discovers its residents have witnessed limitless bloodshed and carnage over the last 50 decades – and each horrific event seems to have occurred 27 years apart...

"We are telling the stories of the interludes, that include interviews [Mike] conducts with the older people in the town," Muschietti, who directs four of the eight episodes, previously told Entertainment Weekly. "In Welcome to Derry, we touch on the usual themes that were talked about in the movie – friendship, loss, the power of unified belief – but this story focuses also on the use of fear as a weapon, which is one of the things that is also relevant to our times."

Set in 1962, it centers on Mike's grandparents Charlotte (Taylour Paige) and Leroy (Jovan Adepo), after they move to Derry and strike up a friendship with one of the Black Spot's founders Dick Hallorann (Chris Chalk). Elsewhere, Charlotte and Leroy's son Will (Ryan Grant Little) faces off against Pennywise (Bill Skarsgård) with a bunch of other local kids.

It: Welcome to Derry premieres on HBO and HBO Max on October 26 in the US. It'll air the following day on Sky and NOW in the UK. For more, check out our picks of the most exciting new TV shows heading our way or our ranking of the best Stephen King adaptations.