Gross. Fear Factor fans are gearing up for a reboot on MTV — but we bet they don't remember why the daring game show was last taken off television screens.

The original Fear Factor ran from 2001 to 2006 on NBC and was first canceled due to low ratings. The network brought the show back "with even bigger stunts" in 2011 with host Joe Rogan, but it didn't last long.

It was canceled again just one year later, and one disturbing stunt is to blame.

MORE: Remember the Teens From MTV's 'My Super Sweet 16'? See What They're Up to Now!

Audiences had seen it all on Fear Factor, but one eating challenge hit a new low for the show when they asked contestants to drink (drum roll please) donkey semen.

fear factor getty

Joe with Brynne and Claire.

When news of the stunt leaked before the episode, titled "Hee Haw! Hee Haw!,” aired, audiences were rightfully disgusted and the network pulled the episode, and ultimately the show came to an end.

Twins Brynne and Claire Odioso were on the controversial episode of Fear Factor and went on to describe the unaired challenge and called it the "hardest 15 minutes of (their) life."

MORE: See How the Cast of 'The Challenge' Has Changed Over the Years!

“If you vomited you would have to start over, I ended up just vomiting in my glass and drank that. The camera men were vomiting,” one of the twins told Gawker. “It smells. It’s so bitter, and it has a little hint of hay.”

However, a source wanted viewers to know contestants had another option during the challenge: donkey urine.

"I'm sure that the contracts caused the talent to agree to do anything and everything, including eat/drink things from animals. Typically you even accept the fact that you might die in the show and you release all liability,” a source told Fox News. “They eat bugs, rats, etc., all the time on ‘Fear Factor’ – and I know that the network tests all challenges before using them to make sure they're safe. So legally, NBC is very likely covered."

Let's hope the reboot, with new host Ludacris, doesn't make us sick to our stomachs.

Fear Factor will re-premiere on Tuesday, May 30, at 10 pm on MTV.

More From Life & Style

'Jersey Shore' Then and Now: See How Much the Cast Has Changed Over the Years!

Find out What Brooke Hogan, Kelly Osbourne, and More Reality Star Kids Are up to Now!

See What the Cast of 'Jersey Shore' Looked Like in Their High School Yearbook Photos!