For most young people, Halloween is all about the sweet loot. It’s about bite-sized Snickers tossed into bags with miniature packets of Twizzlers and Skittles and that candy with the grandest of names and the most meh of tastes, Milky Way.

But 15-year-old Chase Bellows can’t remember the last time he went trick-or-treating.

Maybe he was 10. Maybe he was 11.

“I think it’s been four years,” he says. “But I don’t really mind.”

He stopped knocking on doors with friends not because he dislikes the holiday. He stopped because he really, really loves it. He stopped because he wanted to spend that evening giving his D.C. neighborhood — and the strangers drawn there each year by homes that tend to hand out full-sized candy bars — a haunting experience.

His neighbors in The Palisades already know that as soon as the sun sets on Oct. 31, the teenager’s garage will open to visitors, and inside, they will find carefully crafted decorations, eerie music and costumed actors ready to jump out with terrifying timing.

They will find scenes that took Chase months to put together and that show an impressive attention to detail — and not only because of his age.

The focus the work takes does not come easy to Chase, who is a ninth grader at the Lab School of Washington, which describes its students as “learning differently.” He was diagnosed years ago with severe attention-deficit/hyperactivity disorder, or ADHD.

“It makes me really distracted,” Chase says. He explains that he can go from sitting in class to noticing a squirrel outside the window and suddenly his thoughts are chasing that squirrel. “It’s just like a distraction, a distraction, a distraction everywhere.”

But for his haunted creation, he uses the very skills that, even with medication, can be elusive for him: concentration and commitment. Months before Halloween, he starts brainstorming ideas, planning out the space and searching for bargain-priced props. On the day of the holiday, he does the makeup for all his friends and puts the final vivid touches on the scenery outside the family’s home and inside their garage.

“That requires an incredible amount of dedication and focus,” says his mother, Melina Bellows. She recalls how after the arm broke on a figure outside their home, her son called the manufacturer and when he didn’t hear back from anyone, went to Home Depot to find the right adhesive. “We all have our challenges. But if you can find your passion, you’ll find a workaround. He just works tirelessly on this.”

As we talk on a recent evening, she points toward a fog machine. The white smoke spilling from it contains a strange, yet familiar scent. It takes a moment, and a few deep inhales, before I recognize the smell of a hospital. Think Vicks VapoRub. Chase found the special fog online while looking for items that would fit this year’s theme of asylum.

All across the family’s yard are items that he has given a lot of thought toward. Some he found at bargain shops. Others he pulled from dumpsters. A few were given to him as birthday and Christmas presents.

From his grandmother, he received a towering white figure in a pinstripe suit with wispy black hair. “I am everywhere,” it says. “Come to me, my children. Come with me. You are all my children now.”

Several steps away, a child-sized doll dressed in a stained sailor shirt sits on a battered red tricycle. Chase found him in an antique store on Maryland’s Eastern Shore. The conversation with the salesman, he recalls, went something like this.

Salesman: That thing is creepy. We think it’s haunted.

Chase: Perfect.

He still remembers the first Halloween decoration his family bought. He was maybe 5 when his mother brought home a 6-foot-tall dancing Frankenstein. “It was the funniest thing ever,” he recalls.

Chase was about 10 when he first turned his garage into a haunted space. That year, it wasn’t scary at all.

“Now, people are hesitant to go in,” he says. “There were people that cried last year.”

Last year, when the theme was “toy factory,” between 200 and 400 people shuffled through the small space in one night, the teenager and his mother estimate. This year, they are not sure how many to expect.

“The kids in the neighborhood look forward to it all year,” Melina Bellows says. “They start their Halloween here and end their Halloween here.”

Those who come this year will find themselves walking through a maze of white sheets hanging from the ceiling. They will pass by yellowed and tattered posters that show “missing” people and “rules for patients.” And before they exit a minute later, they will feel long strands of dangling hair brush against them and watch actors, played by Chase’s friends, pop out unexpectedly.

“Where your foot is, they’re going to reach out,” he tells me during an early tour.

As the 15-year-old talks, he holds a plastic severed hand as if it’s an empty water bottle. The more animated he gets, the more the lifeless limb moves. After he reveals some of his creative secrets, such as how he rubbed oats and acrylic paint together to create one doll’s frightening appearance, I ask him to show me what he is most proud of. He can’t decide.

“I’m kind of proud of everything,” he says. “That I was able to do this in two months. This is a big thing for me. I have to focus on one thing to get it done, and it can be really draining sometimes.”

In years past, the haunted experience has been free. This year, Chase will ask visitors to leave one piece of candy as an entry fee.

He and his mom plan to donate whatever is given — Milky Way bars and all — to the Mattie Miracle Cancer Foundation, which distributes the candy to hospitals and nonprofits that assist children with cancer and other needs.

Once Halloween ends, most young people divide their sugary treats, put away their costumes and fall back into their normal routines. Chase will still have work to do. He has to clean the garage so his mother can park her car in it again. He also plans to search Halloween sales for items he can use next year.

Already, he is thinking about that display. This year, his mom vetoed his suggestion to use a chain saw prop. She also — once again — told him he could not expand his creation into the house.

“But next year,” he tells me, “who knows?”

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