1974, Eric stares down at his test, the classroom long emptied around him. One final glance, he walks it up to the teacher. A pass—just barely.
​
In the hallway, its mostly quiet, lockers clank in the distance as the last stragglers vanish into summer. Then, Macie shoves a flier into his chest. She already knows what they’re doing tonight. No Evan’s end-of-school party for them. They’ve got other plans.
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The flier reads: All-Night Swim Party. The address is far—but Macie, as usual, isn’t worried. They’ll just “borrow” Eric’s dad’s convertible.
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Later that night, Eric dozes in his room listening to music. The sky is black. Tap. Tap. Tap. Macie grins from the other side of the glass, ready to spring him loose. She’s good at talking him into things he shouldn’t do.
Moments later, they’re rolling the convertible down the driveway in neutral, holding their breath until they’re far enough to fire up the engine and take off.
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Macie navigates with the map. The drive is freeing—school is out, summer is here, and they’re infatuated.
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Eventually, they reach the address on the flier. But there’s no house. No pool. Just trees. They’re in the forest, alone: a rarity for 17 y/olds. Without reservation, they capitalize on the opportunity to explore together.
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In the woods, Macie hides from Eric. He’s spooked but her actions feel like welcome banter when he finds her. They kiss.
They’re interrupted by a strange tweet. In that direction, something catches their eyes—a glow rising from the ground. Curious, they inch closer to the opening of a large hole.
Without warning, Macie slips and vanishes with a splash, scaring the bird who called them out of the hole. She’s fallen into a crater filled with water—part of the large opening was overgrown.
Eric, panicked, doesn’t think. He jumps in after her.
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The cool water ruins their warm night. The walls of the crater are steep and coated in slick moss. Macie is furious—Eric's decision to jump was reckless and now they’re both trapped. They tread water, yelling for help into the empty woods. No one hears.
Eventually, Eric manages to boost Macie to a small ledge, but it’s no use. She can’t hold on. Their other efforts prove futile.
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Morning bleeds in. They’re exhausted and barely keeping afloat. They speak in goodbyes.
Then, a shadow crosses the rim above. A man appears. He’s calm and says nothing until after he lowers a bag of food and an inflatable camping mattress down to them. His only words: “I’ll be back with help.”
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They devour the food like animals, collapsed onto the makeshift float. For a moment, there’s silence. Then—bubbles. The mattress is slowly deflating, riddled with pinholes.
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Worry returns for Eric but for Macie, it’s a full-blown panic attack. Eric tries to calm her and finally gets her to speak through her hyperventilation.
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She explains an experiment she studied in psychology class.
(SEEN VISUALLY)
1957. Dr. Curt Richter and his lab assistant, Marcus, dropped rats into buckets of water to measure how long they could swim before drowning. 15 minutes, typically. But if they were pulled out, dried off, and dropped back in? They swam for 60 hours. Potential rescue gave them hope.
The man who lowered food: Marcus. He's older now. Marcus never went to get help, He’s still there, sitting next to the crater reading a newspaper with a flashlight, just out of view. It’s dusk and Marcus notices silence. He peers down.
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Macie and Eric float face-down in the water. The experiment is over; Marcus stops his watch and walks away.
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A van pulls up, Marcus climbs out. With a winch, he lowers a rope basket into the crater to fish out the teens. First Eric, then Macie.
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As Macie’s body rises, something slips from her mouth—a reed. Knowing the appearance of death was their only hope for life, they tricked Marcus.
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With the bodies out of the hole, Marcus turns to retrieve something from the van. Eric and Macie bolt.
Shouting, firing wildly into the night, Marcus chases them—he’s manic. Trees whip past them.
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Eric trips into a hole, but this time, its smaller. They hide. Macie and Eric asses their surroundings as they gather their breath. The hole is too perfect. There’s fresh dirt piled beside them. A shovel primed to dig.
All around, filled-in holes litter the forest floor. Graves. Dozens. Marcus has experience.
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The maniac approaches. Eric swings the shovel and drops him. Out cold.
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Together, they push his body into the open pit and bury it clumsily. They run.
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Back at the car, Eric turns the key and throws it into gear. When looking left to make his right hand turn onto the road, Eric notices a parked car with its interior light flickering off. It's strange but there’s no time to investigate. An abysmal drive ensues.
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Neither knows what to say. Macie curls up in the passenger seat. Eric drops Macie off at her house.
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When Eric returns home, the driveway is filled with police cruisers and neighbors. His parents, Macie’s parents—everyone's there. A search party was about to start.
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Weeks later, Eric sits in the passenger seat of his mom’s car. They pull into a drab building. She tells him the state recommended this psychologist, take it seriously.
He doesn’t notice the parked car outside—the one that caught his eye when leaving the forest.
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Inside, they wait.
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The door opens and Macie steps out first. She glances at Eric with a forced smile. Nothing more.
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Then, Dr. Richter walks out.
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The mastermind.