Yes, this actually happened.
The former Special Forces soldier said he was almost killed during his encounter with the ape, and found himself needing serious medical assistance to get his arm back on properly afterwards.
He was only 10 years old when the incident occurred.
Speaking to YouTuber creators The Mulligan Brothers, he explained: "There was a large part missing... half my arm was just hanging off."
The whole thing started back in 1980 when Ollerton was just a boy. He stumbled across a travelling circus near to his home in Burton upon Trent with his brother and decided to investigate.
He said: "We were just crossing the River Trent - across the bridge - when we saw the big top setting up.
"We were so excited that our walked turned into a run - and before we knew it we were at the circus."
Eventually, one of the circus workers showed them around, and Ollie found himself face to face with a baby chimp.
He continued: "I could see some light partially coming through the door. And I walked over to it.
"As soon as I opened the door, the sunlight hit me in the face, blurred my vision and then, all of a sudden when my vision cleared, I saw something that was amazing. Something that had me in a semi-state of shock.
"To me, this was like a little piece of Hollywood. I was brought up on cats and dogs. This was a baby chimp in Burton upon Trent, Staffordshire."
However, things turned sour very quickly.
He continued: "All of a sudden, the serenity of that moment was broken like a fighter jet in the sky when I heard the roar of something. I'll never forget that roar. I can still hear that roar to this day.
"As I looked into the background, there were some shadows - there was a trailer parked there, but the whole area was enclosed - and something was moving. And it roared again."
The chimp's mother had arrived to protect his baby.
Ollie went on: "It was making its way towards me at Mach 10.
"It was doing the whole sideways chimp thing. And it was roaring. It was absolutely ferocious.
"It wanted to do one thing - and that was to kill me and protect its baby.
"I was like a deer in the headlights, but I thought, 'S***, I've got to move.'
"And as I thought that, this chimp pounced straight through the air - it must've been about 20ft - straight over the baby chimp.
"And all of a sudden, the blue sky turned to black and this thing landed on top of pinned me. It pinned me to the floor and started going about me trying to kill me.
"It was like a drummer in a rock band. It was smashing down with its fists onto my chest. The first one winded me - knocked everything out of me - then it started trying to kill me.
"At one point I looked up and I knew that if I didn't do something I was going to die."
He did eventually manage to escape, but not before being badly injured by the animal.
He added: "That gave me just enough space just to scurry away and then this chimp got up and it came on its final attack to kill me."
Were it not for a chain around the chimp's neck, he believes he would have been killed. At this point, a woman who worked for the circus approached him.
"She put her hand around my wrist and turned it over," said Ollie. "And she was in a state of shock. And as she turned it over... half my arm was just hanging out.
"That was the worst damage. There was blood everywhere - and she pretty much fainted."
Now though, he's learned his lesson.
He said: "I had to step into the short-term discomfort for any long-term gain. The long-term was living that day - the short-term discomfort was taking the fight to the chimp.
"That's how people live their lives. They're not prepared to step into that discomfort knowing that on the other side of that is the long-term gain.
"The way we're wired, and this is the way people operate, is everyone is taking short-term comfort. Whether that's drugs, drink, relationships, job choices - all the choices they make knowing that there's a level of comfort there.
"If you want to achieve anything in life, you need to take short-term discomfort for long-term gain."
Righto then. Let's just skip the horrendously traumatic experience with an ape though, OK?
Featured Image Credit: YouTube
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