"I will f--k you up, you literal f--kng c--t," Kourtney yells at Kim before chucking a boxed water at her.
The KKW founder and her sister then begin to fight, with Kim attempting to punch and kick Kourtney. At the same time, Khloe Kardashian tries to break them up.
"Stop you two!" she tells her sisters.
As the fight heads over to the wall, Kourtney then appears to slap Kim right in the face.
"Just get the f--k out of here," Kim says. "I don't even want to see your f--king face."
"I'm getting the f--k out," Kourtney yells. "I don't want to be near your fat ass."
The entire clip is narrated by Khloe, who is dressed as her mom, Kris Jenner.
Reading from the "Great Book of Kardashian-Jenner Tales," Khloe says in the voice over, "Once upon a time, there lived a powerful queen who gave birth to five princesses, each with their own gifts and passions, from health to beauty to humor."
She continues, "But as their kingdom grew stronger, so, too, did the burdens that came with it. Oh, you want to know what happens? Well, honey, you've got to stay tuned."
The wild preview also teases Kylie and Kendall's Kylie Cosmetics collaboration, Khloe learning about her BFF Malika Haqq's pregnancy, and more.
Watch it all go down in the clip, above.
"Keeping Up with the Kardashians" airs Thursday, March 26 at 8 p.m. ET on E!