Amanda Presswood was in her upstairs bedroom last month when she checked her Ring doorbell camera to see if it was raining. It was dry out.

She watched as two cars drove down the quiet street beyond her porch.Christine Peck was spooked by what she saw via the Ring camera in her empty kids’ shop. CHRISTINE PECKThen she heard voices.The first was a male voice, followed by women’s voices.

The speech was garbled, but to Presswood it sounded like the male voice asked, “Can I talk to you?” There was nobody on camera.Presswood lives with her adult son in a 93-year-old house in Galesburg, Ill., a small town not far from the Iowa border. The school-bus attendant had been spooked by unsettling anomalies before—footsteps when no one’s around, the TV suddenly powering on—but she figured there was a reasonable explanation for this incident.“I’ve watched those paranormal shows and a lot of the stories can be debunked, so I tried to debunk it,” she says.Her son wasn’t home.

Presswood knew her neighbors weren’t home either, and that no one was at the church across the street. She panned around with the camera and didn’t see anyone.

She went outside but there was no sign of anyone.Amanda Presswood heard voices on her Ring camera, but no one was around. — Amanda PresswoodSo far, her ghostly story remains a mystery.Home-security cameras are meant to reduce the anxiety we feel from the unknown: Who’s at the door? How is the baby sleeping?

What’s happening at home when we’re on vacation? And these cameras do provide solace, occasionally serving to prevent problematic behavior and even criminal acts.There are cases, however, when the video feed only fuels our worries.

And in rare instances, what we see can be inexplicable—or downright terrifying.Christine Peck, owner of the Sock Monkey Kids Shop in Cape May County, N.J., received a motion alert from the store’s Ring camera one day in August 2024. The shop was closed.

She figured an employee had left something and had gone in to retrieve it, but no one was inside.Instead, she saw a black shadowy mist drifting around the room filled with toys.Mysterious things have happened at the shop before. Several times plush toys have fallen off shelves with seemingly no intervention.

The wispy apparition was the last straw. She turned off the camera alerts.“I don’t look anymore,” she says. “I don’t want to know.”Peck’s area actually made this year’s list of spookiest cities in America: Cape May was ranked sixth by home-security company Vivint.

The company creates its ranking based on reported ghost sightings and haunted locations, among other criteria.Ken Weeks would concur. Two years ago, he was at his winter home in Sanford, Fla., when he got a door alert from the Samsung refrigerator in his house in Cape May.

Sure enough, on his Ring camera, he could see the door open slowly on its own. He even heard the ding the fridge makes when someone waves their hand under the door sensor to open it.

He got chills.Ken Weeks received a notification that his refrigerator door was open. When he checked his camera, he got chills.

KEN WEEKSWeeks asked a neighbor to check the house. Nobody was there, and there was no sign of entry.“Being a skeptic, my first reaction was that it was a technical glitch,” says Weeks, who works for a software company. “But we haven’t been able to come up with a rational explanation for how that happened.”The door hasn’t spontaneously opened again—though some people have complained on Reddit about the same model opening randomly.

Samsung didn’t respond to requests for comment.Not all unexplained occurrences are unwelcome.Emily Pendergast, an actress in Los Angeles, had set up a SimpliSafe indoor camera with her husband in the spring of 2024 so they could keep tabs on their new rescue pit-bull-mix puppy, Winter.One day, while out grocery shopping, they got a motion alert. Her husband pulled out his phone.“He stopped dead in his tracks,” Pendergast recalls.For a moment, they saw what appeared to be Lang, the beloved rescue shepherd mix they had had for nearly 13 years.

Only Lang died in 2023.When they saw this camera aberration, Emily Pendergast and her husband thought it looked like the ghost of their beloved dog. EMILY PENDERGASTPendergast held on to the video and watched it over and over again.

Earlier this month, she decided to post it on Instagram because she felt it might bring comfort to others who have lost pets. The video garnered more than seven million views.

Pendergast likes to think Lang is watching over Winter.“I felt we were able to see something we weren’t intended to see,” Pendergast says.Write to Julie Jargon at Julie.Jargon@wsj.com