It's the last thing you want to happen when you're underground in one of the most haunted buildings in the country with a ghost hunter – their equipment starts going haywire.
Standing in the dark corridor underneath Canberra's National Film and Sound Archives is eerie enough as it is, without a meter detecting unexplained electromagnetic activity.
While by day it's now dedicated to collecting and preserving the country's audiovisual heritage, some of the Acton building's 80-something-year history is a tad darker. It started as the Australian Institute of Anatomy, where it played host to countless forensic examinations and also served as a morgue. It also housed hundreds of human skulls and body parts, most notably Phar Lap's heart. There's also some claims it was home to Ned Kelly's skull at some point.
Since then, the building frequently makes "most haunted" lists, plus there's the endless spooky tales from former workers, including the contractor who claims to have been pinned against the wall by something he couldn't see.
Intrigued by the stories, Dan McMath, and his team of paranormal investigators from Ghost Hunters of South Coast and Territories – or GHOST for short – made their way up from the NSW south coast to spend the night. They also invited fellow investigators West Sydney Paranormal Research, or WSPR – acronyms are big in this game – with nine investigators setting out to see if they could record any paranormal activity.
An incident when he was young ignited McMath's interest in the paranormal. At their family home in Narromine just west of Dubbo, McMath, his sister and his mother heard a commotion from another room, and when they went to investigate, saw that three ornaments sitting on a mantelpiece had flown across the room and hit the ground. The next night, exactly the same thing happened. By night three, they were there to watch it happen again.
"We noticed the last ornament that was on the mantelpiece flew across the room as if someone stood behind it and flicked it. Mum freaked out and I'm pretty sure from memory it was only about two months later we moved from the house," he said.
It was something that fourteen-year-old McMath couldn't completely explain then, and which he's still trying to answer now.
"I've never witnessed anything like it since. It's been personal for me – I've been needing to find out what made this particular occurrence possible.
"The only logical reason I can come up with is completely illogical and that's that it was a ghost."
From there, his "morbid fascination" grew – from reading books and going on ghost tours, through to eventually purchasing all the gear and getting a team together. Now, outside of his day job, McMath is called upon often to investigate unexplained happenings.
"You get people who ring up and contact you and they might ask you to come have a look at their house because they have something weird going on and 90 per cent of the time when you go over and it's something logical. There are a lot of normal things within our world that can cause what people like to call a haunting," he said.
"But one in 10 times, there's something going on we can't explain."
The most interesting thing about McMath is he's the last person who would ever try to freak you out – if anything, he's more of a sceptic than most.
"You have to be sceptical, otherwise you're just fooling yourself.
"We're not quite sure 100 per cent if ghosts exists yet – there's a side of paranormal investigators that believes and knows that there's something that's going on but we can't tell you exactly what it is."
It's the reality that many hoping for a paranormal experience don't want to be told.
"I had to put something on my Facebook page saying, 'if you don't want an honest answer, please don't send me any more photos'. Because nine times out of 10 it's explainable.
"When people say they want your opinion on a photo, what they're really saying is 'can you validate this photo for me as a ghost?', and when you say 'it's not', they get upset."
But he's still had enough unexplainable encounters to keep him searching. When they do capture something, McMath says it's generally in the form of disembodied voices on digital recorders, or interaction with equipment.
"I was touched for the very first time last year at Cockatoo Island. I always heard stories about people being scratched, hit, kicked and I'm not like that – I depend on the equipment to try and gather data.
"But for the first time I actually felt the sensation of fingers grab my arms and that sent me in a different direction of my way of thinking of paranormal."
For their overnight visit to the NFSA, the group covered the Arc Cinema, the gallery, the library, and of course, the notorious basement area. These days, ghost hunting is a technological game, and the crew was armed with everything from electromagnetic field meters and disturbance sensors to motion sensors, static sensors and digital video and audio recorders.
They're still working their way through hours of audio and video recordings, but a few findings have already surfaced.
"In the main gallery I thought I witnessed a black shadow dart across in front of me. When we went back into the gallery a few hours later we were talking about this, and we did physically hear someone yell out. We can't figure out what they were saying but we did hear it which was quite weird," he said.
"One of the guys from WSPR had an infrared Go Pro on his head – he thought he saw a shadow in the basement area underneath the bowels of the NFSA – I think they may have caught that shadow."
Also from the basement, right near where Ned Kelly's skull was rumoured to have been found, they got some unusual audio recording.
"A few of the guys were down there asking some questions and the responses they got were some weird clicking sounds. They were in direct response so they were asking 'can you make that sound again' and bang you got this weird clicking sound on the digital recorders.
"The guys have never heard that before, I've never heard that before. Whatever's caused that clicking sound is up for debate, but we can definitely rule out any kind of malfunctioning of the equipment."
McMath said it's too early to draw conclusions about the NFSA, although he believes there "could be something going on there – we definitely had a few experiences". The investigators tend to visit a venue two or three times to get a thorough feel for things, and McMath is already in talks to come back in the coming months.
And as for the meter that went off while we were in the basement?
"Look, that surprised me. And I can't figure out a logical explanation why. Because there was no one else in the building … there was nothing that would have been activated that would have caused a high burst of electromagnetic field to make my meter do what it did.
"I took a normal base reading when I was there during the night and there didn't seem to be anything going on. So to have something go off while we were doing the interview when there was no one else in the building and no extra equipment was activated. Yeah that's perplexing to say the least."
Tim the Yowie Man runs regular ghost tours of the National Film and Sound Archives. Tickets are $70. For tour dates and bookings visit nfsa.gov.au.