A “Don’t be a Monster” sign hangs in the wardrobe and makeup room of the popular Denver haunted house attraction 13th Floor where actors and actresses are literally dressing up to be monstrous creatures.

“We train them to be respectful when scaring people,” said Wardrobe Director Wesley Green. “There’s a difference between a good scare and a mean scare.”

That’s just one of the secrets to running a successful, and profitable, haunted house.

The 13th Floor, which is one of the longest running and most popular haunted house attractions in metro Denver, has been delivering screams, jumps and the creepy-crawlies since 2008. It started on Brighton Boulevard in north Denver’s River North (RiNo) neighborhood, but the soaring real estate prices there forced its move to the current location of 3400 E. 52nd Ave., Denver.

“When you look at our business on paper, the profit/loss and the brick-and mortar expenses year-round, you see something very similar to other businesses,” said 13th Floor Entertainment Group CEO Chris Stafford. “The only difference is our revenue stream is concentrated into a few months. It’s hyper-seasonal.”

The complex also offers year-round offerings like axe throwing, a “Blitz Bowl” bowling-with-a-football game, and an escape room – but Halloween brings the throngs of crowds.

Stafford is from Denver and said his background in haunted houses goes back to when he worked at one as a teenager. It’s where he met his future business partner Warren Conrad and the two talked about what they would do to make the best haunted house. They collaborated in 2001 and opened a Denver haunted house called the Nightmare Factory, which later became The Asylum. It wasn’t until 2008 that Stafford quit his banking job to devote all his efforts to haunted houses.

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A 13th Floor Haunted House performer poses for a portrait before guests arrive at the haunted house on Tuesday, Oct. 12, 2021 in Denver.

“We originally opened a haunted house as a hobby – all we wanted to do is celebrate Halloween with the intention of creating good memories, like we had as teenagers,” he said.

Now the company operates 15 haunted house attractions across the United States, including Chicago, San Antonio and Austin.

This year’s house has three separately themed areas: Frost-Bite, cryogenic zombies; The Dollmaker and Bad Blood, where the vampires and werewolves face off. Also new this year are the ShriekEasy Bar for guests to hang out afterwards, and the “SubZero Secret Bar” where patrons can pre-pay for a shot with their admission ticket. It’s almost like a theme-park atmosphere with professional picture taking stations and a merchandise shop.

“Those add to the customer experience,” Stafford said. “They’re not giant profit centers, but add to and enhance the overall experience.”

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Decorations hang in the 13th Floor Haunted House on Tuesday, Oct. 12, 2021 in Denver. 

The experience is sensory overload and visitors encounter fog and smoke, sharp cracking and popping sounds, screams (from visitors and actors), motion-activated creatures and experiences (like unexpected bursts of air on your legs) and even piped-in scents, like pine trees in the haunted forest. Actors blend smoothly with the static creatures, so you never know if they’re going to move. The ground sometimes shifts under your feet. They’ve also mastered the art of scary deception – visitors’ eyes are drawn to one area, while an actor or effect gets you from an unexpected place.

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“We always take our cues from pop culture, what’s popular in movies and television and the current horror genre,” Stafford said. “We aim for a PG-13 type atmosphere where the scary parts appeal to adults, and younger people. We don’t recommend the 13th Floor for kids under 12-years-old. … We try to go right up the edge, but not offensive.”

The company employs about 25-30 year-round, including one fulltime employee at each location. But when Halloween season comes around, its payroll grows exponentially.

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A 13th Floor Haunted House performer poses for a portrait before guests arrive at the haunted house on Tuesday, Oct. 12, 2021 in Denver.

“In 2019, we ended up cutting paychecks for about 3,500 people,” Stafford said. “One of the challenges of this business is hiring that amount of people in a short amount of time. It became a lot harder this year.”

Christina Holguin, 25, of Denver, has worked as an actress at 13th Floor for eight years. Ironically, she works with blood for her day job – she’s a phlebotomist (nurse technician who draws patients’ blood). But this night she’s a zombie in Frost-Bite.

“I started here because I just love Halloween,” she said. “It’s fun being able to scare people and see them enjoying themselves.”

She said the key to a good scare is unexpected body movement and perfecting a “deep, raspy voice – not just a creepy voice.”

Stafford explains the art of the scare like this: “It’s all a science, and we do it safely. An intimidating monster lurking in the corner sometimes can scare more.

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A 13th Floor Haunted House performer poses for a portrait before guests arrive at the haunted house on Tuesday, Oct. 12, 2021 in Denver. 

“Overly-intimidating doesn’t work. If they get right in your face, but don’t attack you – the threat has gone away and you’re not suspending disbelief anymore. We’re respectful of personal space but can be a lot creepier.”

He said technology has improved tremendously in the last 10 years, allowing for “completely different props and effects.”

“It’s not just a black wall with jump-out experience, these sets have high production quality,” Stafford said. “Some say they’re movie quality – but I think they’re a little better than that because you have to walk through them and live in them as an experience. That’s the biggest way the business has evolved.”

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A 13th Floor Haunted House performer poses for a portrait before guests arrive at the haunted house on Tuesday, Oct. 12, 2021 in Denver.

The Halloween holiday has grown in popularity in recent years for two main reasons, he said. First, it’s grown from just an American holiday to being celebrated around the world. Second, the way we like to entertain ourselves has changed.

“Our core business is selling the experience,” Stafford said. “Nowadays, people want to actively participate in their entertainment. They don’t want to be passive observers. … Plus, a lot of people like to play dress up.”

Recent visitors from Kentucky said they got their money’s worth.

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A performer at 13th Floor Haunted House gets their makeup done before guests arrive at the haunted house on Tuesday, Oct. 12, 2021 in Denver. 

“That’s probably the best haunted house I’ve ever been to,” said Kistyn Graves, 28, of Lexington, who came with her husband Darin. “It’s sensory overload and keeps you on your toes. I mean you know it’s not real and you’re safe, but it sure was scary.”