NEW YORK (AP) — Deep in a cavernous New York City warehouse, the artisans behind some of the world's most beloved children's characters have been fashioning costumes and puppets for years in relative anonymity.

Now Jim Henson's Creature Shop, the workshop founded by the legendary creator of the Muppets, is drawing back the curtain.

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This year, the company opened the doors of its Queens workshop to public tours for the first time, allowing fans to meet a puppet builder, see a puppetry demonstration and take photos and videos with beloved and iconic characters.

Jason Weber, the shop's creative supervisor, said the tours, which cost $150 a person, are an opportunity to celebrate the unsung craftspeople that bring these famous characters to life.

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"There is a level of expertise here that we're sharing. It's not just going to a pop-up store or something like that," he said during a recent visit. "Things are made one-of-a-kind, made by hand with artisans who have been trained for years and decades."

Besides Kermit, Miss Piggy and other Muppets, Henson was the creative force behind Big Bird, Cookie Monster and other famous "Sesame Street" denizens, as well as the "Fraggle Rock" characters. He died in 1990.

Henson originally founded the workshop in the 1960s in Manhattan and it has moved multiple times around the city since. It's been at its current location in Queens since 2009. The company also has a workshop in Los Angeles, though that doesn't offer tours.

The 80-minute New York tours take place on Saturdays. Visitors start in a large room specially created for the tour that's filled with real show props and creations. It's also the only spot on the tour where visitors are allowed to take photos and videos, as much of what's in the actual workshop are still works in progress or proprietary.

"The Muppets" are now owned by Disney. Sesame owns the rights to Big Bird and other characters Henson created for the long-running show, which films at a nearby studio.

Among the centerpieces in that first room on the tour is an Oscar the Grouch display where the "Sesame Street" character is in his familiar trash can surrounded by heaps of fake garbage.

There's also a menacing black throne from "The Dark Crystal," Henson's 1982 live-action fantasy film, and a full-sized working puppet of Junior Gorg, a giant from "Fraggle Rock," which requires multiple performers to manipulate.

The workshop space itself is filled with fantastical creatures in various stages of assembly. There's drawers and bins tucked into nearly every corner brimming with colorful furs, textured fabrics and ready-made puppet body parts, clothing and accessories.

"Everything we do is custom. Everything we do is bespoke," said Melissa Creighton, the shop's director.

On a recent visit, staff were busy preparing costumes and other pieces for a range of current projects, including a "Fraggle Rock" musical opening later this month at a theater near Times Square.

The shop's past credits include the horror movie "Five Nights at Freddy's," the children's fantasy film "Where the Wild Things Are" and the 1990s television sitcom "Dinosaurs."

Sierra Schoening, a senior puppet builder, said working at the shop had been her "pie-in-the sky" dream job. Her favorite movie growing up was "The Labyrinth," Henson's 1986 musical fantasy film starring David Bowie and Jennifer Connelly.

"I just really always wanted to know how those illusions were made," Schoening said as she took a break from fashioning a set of new creations. "I know all the secret sauce, and I'm making the secret sauce now."