Megan Fox "went to Hell for eternity" after drinking ayahuasca.
The 'Till Death' actress and her boyfriend Machine Gun Kelly took part in a spiritual ritual with the psychoactive tea - which induces auditory and visual hallucinations - on a trip to Costa Rica, and she explained the setting was nothing like she'd expected in order to make people "surrender to the experience".
Speaking to guest host Arsenio Hall on 'Jimmy Kimmel Live!', she said: "So we went to Costa Rica to do ayahuasca in, like, a proper setting, with indigenous people.
"So I was thinking it was like glamping, like it was gonna be some kind of five-star experience.
"But you get there and you really are in the middle of the jungle, and you don't get to eat after like 1 p.m. You have to walk a very far distance to get your water, and you can't shower because they're in a drought.
"There was nothing glamourous about it, and it's all a part of making you vulnerable, so you sort of surrender to the experience."
The ceremony began with the group having to "vomit everything" out of their bodies.
She explained: "You all line up at the edge of the rainforest, over this weird fence, and you go three by three and you drink lemongrass tea until you, not by your own volition, just vomit everything out of your body.
"And you have to vomit a certain amount until they let you get back with everyone else, so you're like cheering on everyone as they throw up."
Although the couple had reservations about being sick in front of "20 strangers" at first, it ultimately proved to be "such a good bonding experience" as it got them "ready to go into the ceremony that night" because they lost all vanity.
The ceremony itself lasted three days and was "incredibly intense".
Megan said: "Everybody's journey is different, but on the second night I went to Hell for eternity.
"Just knowing it's eternity is torture in itself, because there's no beginning, middle or end. So you have a real ego death."
But the 35-year-old beauty insisted the ritual was able to help in a way that "surpasses talk therapy or hypnotherapy".
She added: "It just goes straight into your soul, and it takes you to the psychological prison that you hold yourself in.
"So it's your own version of hell, and I was definitely there."
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