“Goosebumps ”Actress Kathryn Long Recalls Thinking of R.L. Stine Like a ‘Creepy Mister Rogers’ While Making ‘The Haunted Mask’ (Exclusive)

The actress admits she didn’t know what to expect when she was cast, but had fun with the once-in-a-lifetime experience

NEED TO KNOW

• Kathryn Long played Carly Beth Caldwell in the ‘Haunted Mask’ episodes of the mid-90s TV series Goosebumps
• Long tells PEOPLE about getting the role in the episodes based on the most popular book in the Goosebumps series
• Long will part with items from the show, including the Haunted Mask itself, in an upcoming Propstore auction

Working with R.L. Stine is an experience most will not forget.

Kathryn Long, the actress who played Carly Beth in the 1995 Goosebumps series, recently caught up with PEOPLE as she prepares to auction off memorabilia from her time on the show with Propstore.

“The first Goosebumps, the pilot episode, I think I was 11 or 12, and I was fairly new to acting. I think I only had an agent for about a year. I remember that we didn’t know it was going to be the pilot. We just thought we were auditioning for an episode. We didn’t know which episode it was going to be,” she tells PEOPLE.

“Then we found out that I got the pilot and I was very excited about that. We shot two weeks just outside of Toronto, and I got to meet R.L. Stine. I think it was like our first or second day on set, which was really fun.”

Finding out that the pilot episode would focus on one of Goosebumps‘ most popular titles was also a thrilling discovery.

“I remember my mom telling me that it was going to be ‘The Haunted Mask,’ which was a very popular book. I remember going back to read it. I just don’t think when you’re that young, it really hits you if it’s going to be iconic or not,” she shares. “You’re just a kid and you just want to have fun. But I think on set when R.L. Stine came and then we all realized it was going to be the pilot, we thought, ‘Oh, okay, this is going to be a big deal.’ ”

Meeting the author behind a series as big as Goosebumps meant a lot to the young actress, who carefully observed Stine along with her costars.

“We couldn’t really get a gauge on his personality because to us, he was like a creepy Mister Rogers,” she recalls. “He was very composed and quite stoic on set, but also had this creepy look about him. He’d used his eyebrows. He was very, very quiet, but I guess very observant.”

In his autobiography, Stine praises Long’s performance as Carly Beth. She laughs, “I’m glad he liked my performance and that we did his story proud.”

“Having him on set was really fun. I still remember having those photos taken with him and me that circulated quite a bit out there. I’m in my mask and I’m posing in the mirror and he’s behind me looking like a child version of a Stephen King situation,” she recalls.

Long is parting with Carly Beth’s Haunted Mask, over 30 years after taking it home as a memento from filming, in Propstore’s upcoming $10 million Summer Entertainment Memorabilia Live Auction, from Aug. 26 to Aug. 29. She was inspired to make the move after attending a recent fan convention and understanding what these keepsakes mean to the devotees who bring them home.

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Consigned directly from the actress’s personal collection, it is the first time Long is sharing the keepsakes she quietly held onto from the role that defined a generation of childhood nightmares. The Haunted Mask is expected to sell for between $20,000 and $40,000, while Long’s annotated script is estimated at $2,000 to $4,000. The screen-matched bust of Carly Beth is also available, estimated to sell for between $15,000 and $30,000.

Recalling watching the props come together, Long shares, “There was a lot of excitement for sure on set. And I think just because it was the ‘90s and there wasn’t CGI and as many special effects, all the stuff was made by artists. So the graphic artists on set, who were doing all of our prosthetics and stuff, which was really an amazing process. I remember we all thought that was really cool seeing all the masks and the prosthetics and being a part of that.”

Of parting with the mementos, Long notes she was hesitant at first, but decided, “Wow, that could be so meaningful for someone to have a part of that history of Goosebumps. And so I thought, this, now, is a good time to part with it.”

It’s far from the end of Long’s Goosebumps story, however. She is slated to appear with Stine, reuniting for the first time since the episode was filmed, in the spring of 2027.

Propstore’s Summer Entertainment Memorabilia Live Auction runs from Aug. 26 to Aug. 29 and is open for registration.