Steve Wesson, 44, visited Manby Hall, in Lincolnshire, earlier this year with his UK Ghost Hunts team and could not believe his luck when he captured the 'freaky' footage.
The team didn't realise that an unknown figure wanders through the background until looking at the video later that night but Steve insists it could not have been any of his team and there was no one else in the building.
Steve believes he must have seen the shape in the corner of his eye as he followed the suspected phantom into a stairwell, which footage shows was eerily empty.
Manby was a key area for the RAF during WWII and the hall was once used as an RAF base as well as an old people's home before closing down.
Steve, from Kimberley, in Nottingham said: "The security guard went in the left room with two of the team members and I was following filming with a camera.
"I didn't hear any footsteps in the corridor neither did the rest of the team or the security guard.
"I must have seen something out the corner of my eye for me to go in there but I didn't really notice it at the time and didn't take any other notice and rejoined the guys, as you can see there are shadows on the back wall cast from our torch light but no shadows cast from the figure.
Read Full Story: Mirror UK