Timothy Buchannan filmed the moment he discovered what appeared to be a creepy bug behind the screen.
The clip shows the little eight-legged creature running across the desk.
"We're pretty sure it's real because he's there no matter what window we put on, he's there," said Timothy.
Indeed, while dragging the different tabs on the creature stays in the same place.
The frightened cameraman touches the screen and the spider immediately crawls to another area on the desk.
Before the video comes to an end, a person outside the camera suggests that the bug may have entered the iMac through the air vents in the back.
Yesterday, Timothy posted the surprising discovery on YouTube, where he wrote: "At first, we thought it was a digital spider, like someone was playing a trick or something.
"But this is real.
"Does anyone know how to get it out?"
And the spectators rushed to offer their suggestions.
"Fire … it's the only way," joked one.
Another added: "Talk to Apple support, they should be able to help you."
Daily Star Online contacted Apple to get their comments.