WARNING: The following contains spoilers for Vivarium.
Vivarium is one of those psychological thrillers that is meant to leave audiences with this suffocating feeling. It revolves around Tom (Jesse Eisenberg) and Gemma (Imogen Poots) as they're duped into visiting a housing settlement in England called Yonder. They're shockingly abandoned by the real estate agent Martin (Jonathan Aris), however, and spend the next few months there.
Trapped in this looping maze, they find a kid on their doorstep in the abandoned development and they're left to raise "the Boy." By the time the finale rolls around and the truth is revealed, though, as much as the film tries to veer into horror territory, it ends up being a weird conclusion that reveals a sinister invasion plot.
WHO IS THE BOY?
In three months, the Boy goes from a baby to a seven-year-old kid, leaving Tom and Gemma wondering what kind of supernatural entity they're dealing with. Gemma tries to raise him with love, but it frustrates Tom and they grow apart. It gets worse as Tom tries to dig an underground tunnel out of the settlement, getting poisoned along the way.
When Gemma asks the Boy where he keeps getting food, reading material and secret messages from, it all comes apart as he mimics some kind of monster. His voice becomes warped and his throat puffs out, like a frog, leaving Gemma petrified. She finally accepts he's not human, but by that point, it's too late. She can't do anything about it and in the next six months, he grows to be a young adult.
He shows no remorse for Tom, though, and when he dies, the Boy bags him and throws him into the hole he dug. This enrages Gemma who tries to kill the Boy with an ax the next day, but after a blow to the head, he hisses and gets down on all fours, crawling around rapidly like an insect. He somehow raises the pavement and escapes, but a nimble Gemma gets inside where she discovers the Boy isn't a demon, he's an alien.
THEY ARE LEGION
In this pocket of space-time, Gemma falls through various houses in the settlement, seeing other parents who were kidnapped by Martin. She witnesses them in the situations she and Tom were in, with some going mad, some fighting, and others even committing suicide. But she also notices various iterations of the Boy and his slightly monstrous forms.
She realizes it's actually a breeding camp for aliens and couples are being abducted to raise them so they can head out into the world. It's why all the houses are numbered #9 as it's a play on nine months in the womb. Gemma starts to understand the aliens wanted her to assume the caretaker's role of cook and cleaner, while Tom would -- as he's a handyman -- fix things around the home with his tools. They were stereotyped and selected as these beings assumed they'd form the ideal home for the Boy.
In the final sequence, Gemma's seemingly poisoned by her trip and gets tossed back to her home. The Boy's then seen a few days later placing her in a body bag as she curses him for mistreating her and Tom. He doesn't care, though, and after she dies, he chucks her in the hole too and departs Yonder in her car. The Boy then ends up at the same agency Martin was at in the beginning but this time, Martin's older and dying. When he perishes, the Boy bags him and removes the body, taking his nametag to confirm the aliens' scheme. They masquerade as agents, kidnap couples or parents, then force them to help the other Boys get out into society. The story concludes with the new Martin meeting a new, unsuspecting couple he intends on luring to Yonder to raise another Boy.
Starring Imogen Poots, Jesse Eisenberg, Senan Jennings, Jonathan Aris and Eanna Hardwicke, Vivarium is now available through major VOD services.