You didn't fall. You were pushed.

Stephanie Silkwood just hit her head. Hard. As she comes to on the deck of a luxury riverboat cruising down the Amazon, she's acutely aware of two things: she bleeding profusely, and her husband Steve is the one who shoved her overboard. At least, that's what her newly faulty memory is telling her.

Beyond the two hot palms against her bare back right before she tumbled over the railing, Stephanie remembers little about the months leading up to the trip or the couple joining them. Doubting her own recollection, Stephanie searches for the truth of what happened the night she went overboard.

As tensions rise, the boat cruises deeper into the rainforest, and their friend Collin insists they finish out their vacation with a night in the Peruvian jungle for a supervised retreat where they will all experience the mind-altering effects of ayahuasca.

What unfolds through the evening is more than Stephanie bargained for, and not everyone will survive until dawn.

She remembers everything.