'Vanderpump Rules' SURver Scuffle: Kristen Doute 'Did Not Have Sexual Relations' With James Kennedy -- Or Did She?
19 Celebrity Cheaters

Kristen loses it in Mexico when the cast begins to speculate she cheated on boyfriend Carter.

"Kristen, I have to say something," Katie Maloney began Monday's episode of "Vanderpump Rules." "When Tom got back from golfing, they said that you and James hooked up."

And so begins the hour-long investigation: Did Kristen Doute have sex with James Kennedy?

"Crazy Kristen" has remained fairly tame this season. For starters, she's madly in love with her non-SUR server boyfriend, Carter. And secondly, we haven't really seen Kristen get absolutely wasted. But that all changed Monday night when the group vacation in Playa del Carmen, Mexico -- sans-Carter -- continued.

Upon waking up the morning after the alleged incident, Jax Taylor told Brittany Cartwright he was certain something went down between the exes because he saw them both drinking tequila together at 8:30 a.m. in their hot tub, surrounded by suspiciously placed couch cushions. He then told the story to Tom Schwartz and Tom Sandoval during their drunken game of golf while James wasn't within ear shot.

"Did you hang out with Kristen last night?" Sandoval asked James when he rejoined the group. "Did I what?" James replied, clearly drunk. "What did you just say? 'Hang out with Kristen?' I mean a little bit, but not really." In Jax language, that was a full-on confession, but James was adamant that nothing happened. He even cried.

Elsewhere, while some of the girls were discussing the incident, Scheana Marie alluded to Kristen having hooked up with James toward the beginning of her relationship with Carter, saying, "I don't think they would, but also didn't think Kristen would've banged him in the car when she did after she started dating Carter."

Lala Kent added, "I believe something happened. Once the dick has entered one of your holes, it's easy for it to re-enter."

Flashback to the episode's opening scene: "Bull f-cking shit," Kristen fired at Katie.

When Stassi Schroder suggested Kristen might have hooked up with James in a blacked-out state, Kristen lost it.

"Don't you f-cking dare! Don't you f-cking dare!" Kristen shouted. "You're gonna piss me the f-ck off right now. I would never. Don't entertain this. I would never ever ever ever ever ever cheat on Carter, and you guys know me. I will not have shit made up about me. I did not have sexual relations with that boy."

"There was a summer where you lied to our faces the whole entire time," Stassi fired back, referencing the time Kristen lied repeatedly about having banged Jax.

The intense climax came during the group's last dinner in Mexico when Kristen called out James for having started the "rumor." She ended up throwing a drink at him, which landed mostly on Lala, which infuriated Lala.

Bottom line: Jax, Schwartz, Sandoval and Peter all took James saying he and Kristen "hung out a little bit" as they "hooked up a little bit."

"Vanderpump Rules" airs Mondays at 8 p.m. on Bravo.

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