That chill creeping up your back — sure, it could be the unseasonably cold weather, the three less hours of daylight, the furnace refusing to kick in, the early-onset flu.

But what if it’s not?

In honor of Halloween, we asked Maine ghost-hunting groups to recount their creepiest, most intriguing encounters.

Get ready to grab a nightlight and maybe look at libraries differently.

‘CAN’T YOU SEE IT, MOM?’

Thirty years ago, long before she co-founded Paranormal Reactions, Terry Astbury was living in a 300-year-old, sometimes-eerie house in Kittery with her 3- and 4-year-old daughters.

“I would see things out of my peripheral vision,” Astbury said. “We had a cemetery in the backyard that my 3-year-old wanted to dig up all the time. When I’d say to her, ‘You can’t do that,’ she’d say, ‘Oh, no, mom, it’s all right.'”

One morning around 3 a.m., she heard floorboards creak and got up to find her older daughter at the top of the stairs.

“I just kept saying, ‘Julie, go back to bed.’ She wasn’t moving,” Astbury said. “The hair on the back of my neck started standing up, just the way she was looking at me. It was just getting creepy.”

Nearly eight months pregnant with twins, Astbury trudged up the stairs and steered Julie back to her bed.

“I started to walk out the door, and she sits up in bed and starts screaming, ‘Can’t you see it, mom? Can’t you see it?'” Astbury recalled.

The girl pointed frantically to the 12 inches between her dresser and bed, but Astbury couldn’t see a thing, and her daughter wouldn’t elaborate on “it.”

By now, the 3-year-old was up, too. Astbury lay down with her, trying to settle her younger daughter, wondering what the heck was going on.

“All of a sudden, two hands went on each shoulder and pinned me to the bed,” she said. “I was scared to death.”

When she finally sat up, she stayed awake until 6 a.m. and went straight to her landlord’s door on the other side of the house.

Had she ever experienced anything weird?

“Oh, honey, things like that happen all the time,” the landlord told her. “Ask my girls about growing up in this house.”

Astbury and her daughters lasted another four months. Twenty-five years later, she was driving by the house and saw the door open.

“I said to my husband, ‘Stop. Let’s ask if we can investigate,'” she said.

The new owner was working on the property, didn’t have a tenant and let them in. The team didn’t encounter anything during the investigation, but discovered during research that a girl had hanged herself in her daugher’s former room. They also collected curious photos of orbs and what they thought looked like a ghost dog.

Today, the house has another new owner. It’s had a lot of them, Astbury said. She finds herself wondering when she drives by if they’ve experienced anything.

Maine Ghost Hunters co-founder Tony Lewis takes part in an investigation of the Anderson Cemetery in Windham, New Hampshire. The Bowdoinham group, which has been ghost-hunting for 10 years, has seen and heard some strange things.

LEFT, RIGHT, GHOST

Not long after forming 10 years ago, Maine Ghost Hunters, out of Bowdoinham, took a new piece of equipment to a Freeport cemetery in the middle of the day to test it out.

The device, known as a ghost box, works by emitting radio signals in the hope that ghosts can try to harness that energy and communicate back, co-founder Tony Lewis said.

“Kat (McKechnie) and I were wandering around and we were asking questions,” Lewis said. “Not a lot was happening at first, but we started understanding what the box was telling us and we understood it to be directions.”

Right. Left. Straight.

At the same time, “it kept spitting out names at us. Eventually, it led us to a memorial at the end of one of the aisles we were walking down,” he said. “We kept thinking we were hearing ‘Timmy.'”

They stood in front of the four-sided monument and found not Timmy but Jimmy, Jimmy Small.

After all the lefts and rights, Jimmy went quiet.

They’d eventually learn he died as a teen when his rifle went off while he was walking back from a hunt.

“Kat was probably more, not freaked out, but on edge about it,” Lewis said. “It gave her the willies to know that there was actually a spirit talking to us in real time and led us right to the tombstone.

“Spirits are around all the time,” he said. “You don’t have to go ghost-hunting in the dark.”

‘KINDA FREAKING OUT’

Central Maine Ghost Hunters — from left, Michael Marshall, Dustin Marcia, Heather Budesheim, Michael Owens, George White and Renee Evans — held a two-night investigation of the Skowhegan Public Library last weekend, inviting the public to join them. Each night, more than 30 people did.

Dustin Marcia’s team’s most recent investigation of 2018? Two nights at the Skowhegan Public Library last weekend.

The weirdest? Their first exorcism this past February, at a couple’s home in Augusta.

Marcia, who founded Central Maine Ghost Hunters, of Skowhegan, in 2012, said he first met the 20-something Augusta couple last December when another paranormal team referred them.

They wanted their home checked out, but during that investigation, “it was pretty much quiet,” he said.

Then the couple got a Ouija board for Christmas.

Via the board, “he asked the demon to scare his girlfriend,” Marcia said.

That maybe backfired, Marcia said. “Anytime somebody read a Bible verse to him, he’d start to freak out and he’d start shaking, like a seizure.”

Marcia reached out to a demonologist in Connecticut for help. There were more twists and turns before the night was over. The pair retold the story during Parafest Maine last summer.

“It’s really nothing like the movies. I can’t explain it really, but movies are fake. Let’s put it that way,” he said.

Friday and Saturday’s investigation of the Skowhegan Public Library wasn’t so wild, but it didn’t disappoint.

Marcia said the team was invited in by the staff to lead a public ghost hunt after reports of unexplained music and the sound of someone walking on the floor overhead. About 45 people joined Friday night, 20 or so on Saturday night — a nor’easter wasn’t going to keep them from ghost-hunting.

They placed a camera in the attic along with a few bells and a ball and cleared the area.

“I got on the radio and I told (the library director) to watch the attic camera,” he said. “I then asked the spirits that were in the library if they could ring the bells in the attic and as soon as I said that, (the director) got on the walkie and she was kinda freaking out a little, and she said the bells were moving in the attic. I wanted to try something new and it was awesome.”