Years ago, before he retired, my dad was a telephone engineer. He'd put lines and extensions into homes and businesses.
He and his mate had a job in a stately home, putting an extension in. The particular estate was/is often used in horror films and there are a few creepy stories attatched to it. When they got given the job, the girls in the office and their other colleagues who were there ribbed them about all the ghost stories, winding them up, and as they drove there, they were also joking around about that sort of thing, taking the mickey out of each other.
They got to the home and took a look at the job. As they had expected the best and cleanest way to put the line in was to go through the cellars and then up through the floor, so down they went.
The cellars were a series of small interconnecting rooms. A couple had stairs going up to the rooms above, most didn't. The first few rooms from the main cellar stairs were quite normal. Dim, somewhat, but often used and with a neutral atmosphere. The further away from the staircase, the creepier the rooms. Dusty, damp, ever more dimly lit. My dad and his mate ran the line through each room, opening the door to the next each time, never knowing what to expect. Soon they were in darkness, relying on their torches, still joking with each other but with increasing nervousness. My dad was fetching their tools from one end of one room and his mate opened the door to the next. My dad heard the door open and then came a blood curdling scream, real terror, and he felt the wind rush past him as his mate legged it, running for his life.
My dad says his heart was racing, but he could barely move from the spot. He turned, somehow, directing the beam of his torch towards the still-open door. He saw a figure looming there. It had blood dropping from its contorted face, its eyes were blank. It was human, but larger than a human and it was right there in the doorway. My dad ran for it. He can't remember if he screamed or not, he just fled for his life.
He caught up with his mate at the main stairs and the noise that they were making attracted the caretaker who had sent them down there. They calmed down enough in the relative safety of warmer, brighter ground floor, and told him what they had seen. The caretaker believed them completely. He began to fill in the detail of the figure they had seen, explaining that he himself had also seen it. My dad and his mate listened wide eyed as the man revealed that the room they had opened the door of was the chapel's storage room, and the ghostly figure was actually a 10 foot wooden Jesus on the cross which had been replaced due to woodworm. It was leaning on the doorframe of the chapel cellar. The man also helpfully informed my dad and his mate that they were a couple of twats. The never lived that down at work, or at home.