It started, as a handful of fabled Challenge fallouts before it, with a collection of misplaced pizza slices. And now, former BFFs Josh and Fessy have come to blows. But can they make nice before their Big Brother estate totally goes up in flames, or is this bromance finally broken up for good?

Since Fessy tossed the Vet Truce out the window by voting Amber (an alleged part of his Big Brother alliance, no less) into The Lair alongside Hughie, Josh — Amber’s partner — has been reticent to trust his former friend. Josh insisted that Fessy demonstrated total disregard with his vote, and on the latest episode of MTV’s competition series, he said Fessy could choose to apologize or suffer the consequences.

“He does what’s best for Fessy…[but] we deal with all the backlash,” Josh lamented to Fessy’s partner Esther. “I’m still pissed off. I’m heated.”

But temperatures would only rise. After Kaycee and Emanuel snagged their first win as partners in “Turning Agents,” a memory game played from the top of spinning-out stunt cars, things went from bad to worse for the already fractured BB alliance.

After a night out at the bar, Amber, who waited patiently for her meatless frozen pizza to cook through, suddenly noticed when she was ready to chow down that it had gone missing. Intent on goading Amber into confronting Fessy, Tori and Cory — who falsely implicated Fessy as the pizza thief — finally got Amber to check Fessy for his underhanded gameplay. The conversation was terse but fair…that is, until Josh entered the picture.

And then everything went to hell.

Fessy insisted that he did nothing wrong by voting Amber, someone he viewed as a dangerous frenemy, into the looming elimination round. But Fessy and Josh saw things differently, and in an instant, Josh went from laying low in the backyard to drawing security into the mix — once again — by stepping up to Fessy.

“You suck as a friend. You got a big-ass ego…you’re the biggest piece of sh** I’ve ever met on this show,” Josh spat while Esther, Fessy’s partner, tossed a drink in Amber’s face (man, these partnerships go way deeper than we remember them going).

“I’ll f*cking dog you and make you look like the big bitch you are,” Josh added.

And Fessy’s fuse grew shorter…quickly.

“You’re supposed to be my best friend, and now you’re airing out my dirt to everybody,” Fessy said as the rest of the cast continued to pass around pizza slices and watch the mayhem unfold. “I don’t know what to do right now.”

Well, knowingly or not, Fessy finally acted. He reached back and smacked Josh’s face backward as the cast and security looked on incredulously. And then, everything went dark.

So what happens now that Fessy’s thrown hands: Is he a goner? Could he and Josh get warnings and finally reconcile? Will they settle the score on The Lair’s battlefield? Share your thoughts, and be sure to check out the next Spies, Lies and Allies on Wednesday at 8/7c.