If there's one film guaranteed to unnerve the sensibilities of even the most hardened horror film buff, it's The Exorcist.
William Friedkin's 1973 classic about demonic possession often tops the scariest film of all time lists for a very good reason. The tale of a 12-year-old girl being possessed by the devil is enough to give the chills to someone with veins full of ice water.
Still, as scary as The Exorcist is -- it becomes a lot scarier when you realize it's based on a true story -- at worst the film will leave you with a few sleepless nights, as well as a lifelong phobia of spinning heads, deep voices, projectile vomiting, upside down crosses, and, in particular, girls called Regan.
Although most of us would dismiss The Exorcist as just a very well-crafted horror movie guaranteed to scare you witless, evangelist Billy Graham once claimed that an actual demon lived inside the celluloid reels of the film.
Judging by her own terrifying experiences, British lady Gina Frost might just well agree with him. Gina watched The Exorcist when it was first released in 1973, and ever since the 57-year-old grandma has been plagued by hellish visions of death and destruction.
The Daily Mirror reported that the first of Gina's vivid and horrifying hallucination began not long after leaving the cinema with her ex-boyfriend.
Tormented by macabre visions of rats scurrying up her walls and other infernal sights, Gina locked herself in her room for nine long weeks. She now claims The Exorcist left her with Post Traumatic Stress Disorder, and is responsible for making the last four decades, as Arthur Rimbaud would say, a season in hell.
"I remember people running out of the cinema to be sick and there were girls screaming behind me," explained Gina.
"It was one of the first horror films I'd ever seen. I remember being horrified at the scene where the priest pummels the young girl's heart with a stake.
"Just one week later I was in my bedroom and I began seeing rats running up and down the walls. I ended up locking myself in my bedroom for weeks because I was so petrified.I thought I was going mad. It took me about nine weeks before I felt like I could go back into the world.
"Ever since then I have been experiencing awful hallucinations that make me feel sick. Often I hallucinate about my own death. It's like I am watching a film in my head where I am being ripped apart and tortured. It is enough to turn anybody's stomach and it makes me feel ill."
Although Gina has learned to live with her visions, they can be triggered by anything from a loud noise to a particular item for sale in a shop.
"Not long ago I was crossing a road and I saw a shop window and I saw a display of Chinese swords and other weapons in the window. Immediately I knew it was going to trigger a hallucination so I had to find a nice quiet place where I could have a cup of tea."
Over the years, Gina's visions have become worse, destroying her social life and leaving her an emotional wreck
"The hallucinations have taken over my life when it comes to social situations. Ever since I was eighteen I have tried to avoid being in social situations just in case I have a hallucination. Between the ages of 18 and 39 the hallucinations were erratic, but over the past then years they have got worse.
"At one point I was having up to three hallucinations a week and each one lasts three minutes. I often feel exhausted afterwards."
Gina was so afraid of her condition that she somehow managed to hide it from her husband John Topliff for 15 years. She was terrified he would think she was insane and either leave or have her committed.
Eventually she summoned up the courage to tell her husband of The Exorcist curse, and he convinced her to go and see a doctor and get help. The doctor diagnosed Gina with Post Traumatic Stress Disorder and prescribed medication.
"When the doctor told me my hallucinations were a classic symptom of PTSD I was so relieved. I had spent years thinking I was going mad and worrying that I was going to end up being sectioned.
"As soon as I started taking medication the hallucinations came less and less. I still have them, but not as much and they're not as bad as they were."
Despite feeling better than she did after watching The Exorcist, Gina has not watched another scary movie and has no plans to become a born again horror film fan anytime soon.
"I haven't been able to watch a horror film since. Everybody says 'The Exorcist' was the scariest film that was ever made and I have to agree because I have never been able to watch another one, so I have nothing to compare it to."