PORTSMOUTH — Spooky season is in full swing, and the owners of one New England restaurant in a small seaside city believe their security camera may have captured a wandering ghost.

This week, the owners and staff of Library Restaurant in the historic Rockingham Hotel in Portsmouth, New Hampshire, encountered a burglar alarm activation at 2:29 a.m. Tuesday inside the restaurant’s Gold Room bar lounge.

Adrienne and Paul Waterman, the married couple who own the restaurant and reside in the building, checked all 14 security cameras they had installed. None detected any motion in the building, and Portsmouth police located nobody within the premises upon arrival.

One outdoor camera hanging above the hotel’s famed lion statues, however, captured a vapory, mist-like presence passing by the device at the exact moment the burglar alarm sounded. Footage shows the presence blows through from right to left and briefly whooshes past again just before city police show up, resembling the “Ghostbusters.”

See the moment captured on video:

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Video is 'inexplicable'

Can it be explained? Adrienne Waterman, who said she is a ghost skeptic, is having a hard time wrapping her head around it. 

“I am an engineer. I deal only in facts. This is inexplicable,” she said.

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Rockingham Hotel's haunted history

The Watermans bought the restaurant, open since 1975, for $3 million in February, and immediately installed the new security cameras. Not once have they gone off before Tuesday morning, Waterman said. 

The Library’s co-owner stayed up for hours after the alarm, trying to piece together bits of information. An app on her phone allows her to see each security camera in the building and whether the cameras caught any motion in the building. 

None did aside from the outdoor camera, which would not have set off the burglar alarm activation without a breach of the building.

“I’ve learned that suddenly I’m nervous about ghosts that I never believed existed. I don’t want to be the one turning on the lights anymore,” Waterman quipped.

The Rockingham Hotel is one of the city’s most prominent properties, and has a history of haunted happenings. It's also a frequent stop for haunted tours. Waterman learned of the famed hotel’s paranormal past through Roxie Zwicker, owner of New England Curiosities ghost tours, and has heard stories of spirits that linger inside the hotel building.

Family of prominent politician built home on-site

In 1785, Judge Woodbury Langdon, brother to Gov. John Langdon, built a home for his family on-site. He was married to Sarah Sherburne and had 10 children. 

One spirit believed to roam the Rockingham is Sherburne’s, who was rumored to have had an affair with Revolutionary War naval commander John Paul Jones, according to Waterman's research.

“The local gossip and the witch hunting began about her reputation, then she died,” Waterman said. “Now the rumor is that she floats around (feeling) guilty. She’s still trying to reconcile her guilt.”

A second spirit said to wander the hotel’s upstairs corridor has been dubbed the “White Lady of the Rockingham.” Portsmouth’s first poet laureate, the late Esther Buffler, was said to have encountered the allegedly gray-haired ghost while living in the hotel and wrote a poem in the spirit’s honor. 

The claim is the spirit is one of a woman who was a summer guest of the Rockingham and tragically drowned in the area, Waterman said. 

Jessica Wade, a server at the restaurant for six years, noted a woman got trapped in the stall of the women’s bathroom during a fire in the late 1800s and perished. 

In 1870, Frank Jones, a brewery tycoon, former Portsmouth mayor and congressman, bought the building and expanded it, though most of the building was ruined in an 1884 fire. The next year, Jones had the hotel rebuilt, and since the 1970s it has housed condominiums.

According to the restaurant's website, the most significant historic event to take place at the Rockingham was the signing for the Russo-Japanese Treaty in 1905.

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“It’s actually been very surreal because I’m a skeptic,” said executive chef Mark Lipoma.

Lipoma said he initially wondered if the "blast of mist" came from a vent outside, but that this kind of mist is usually seen with cooler temperatures.

The Library’s staffers have had their fair share of uneasy encounters, and no one goes alone downstairs beneath the restaurant, where granite and brick secret tunnels are located. Claims have been made that Jones built the tunnels to lead to his Maplewood Farm mansion, his brewery and to the ocean, said Waterman.

“I’ve definitely heard voices coming from the changing room and no one was there,” said bartender Laina Smith.

“I fortunately have not had any tactile experience to share, besides feeling like something was right behind me in the tunnel downstairs,” said server Sahra Mercure. “(I’m) never going in there again.”

Bartender Lauren Brown said she has heard rustling in the women’s restroom downstairs below the restaurant. Waterman said she has seen glasses and potted plants fall from shelves at random.

“There’s definitely enough weird stuff that goes on here to give pause to any skeptics,” Waterman said.

'Epicenter of ghost energy'

The apparent “epicenter" of the buildings' "ghost energy” is located in a corner downstairs where an old phone booth used to be, until its removal last December, Waterman said.

“There’s lots of people who come in here and say there’s high spirit energy in (the restaurant), especially when you go downstairs,” Waterman said.