The beginning of the film introduces us to a massive orphanage called the Grace Field House. Here, several children of all ages live in peace and harmony being taken care of by a single caretaker, Isabella. Everyone calls her “mom” as she is the only parental figure, they have known their entire life. At first glance, the place seems to be close to heaven for the children with no family. They have enough to eat, many friends, a loving parent, and are provided with top quality education. However, there are a few interesting things about the orphanage that make us question its existence.
First, it is surrounded by a fence which the children aren’t allowed to cross. In fact, they have never been outside of the orphanage premises and thus have no idea of the outside world. Next, every child has a number tattooed on their neck and is identified by his assigned number. These innocent kids have always lived in the orphanage, so they don’t really know if their way of life is what people call ‘normal’ or not.
Then, we are introduced to an 11 year old girl named Emma. She and her two best friends; Norman and Ray are the brightest students, and considered the sunshine of the orphanage. One morning, as they chat, we find out that when the time comes, each child is set to be taken to the outside world to be adopted by foster parents.
Today, it is the turn of a little girl named Conny to spread her wings into the outside world. Everyone is greatly excited for her, as they wish her goodbye, asking her to be good to her foster parents. After the farewell, Isabella escorts Conny to the single entrance of the orphanage and waits for someone. A few minutes pass before Emma notices that Conny forgot her favorite stuffed toy. Knowing that the little girl can’t sleep at night without the toy, she is determined to take it to her before it’s too late. As she rushes towards the entrance, Norman follows her behind, but disappointment hits them when they realize Isabella and Conny have already passed through the gate.
The duo now suffers a dilemma; either they return to the orphanage and forget this ever happened or step outside to take just a glimpse of the mysterious outside world. Curiosity takes the best of them, and the kids decide to take just a few steps out the gate.
To their surprise, there is nothing but a single truck parked on the road. When they go near to inspect it, they are met with an utterly horrifying scene. Little Conny’s dead body lies limp on the floor with a plant stabbed to her. The children are shocked beyond words as they stare at the dead body and think of how excited Conny was to start a new life just a few minutes ago. Suddenly, two alien-like creatures appear out of nowhere and the children are forced to hide under the truck.
The creatures discuss their likeness for human meat and one of them claims that the meat grown in this orphanage is the best and is only saved for the elite demons. Here, the children realize the shocking truth about their life; the orphanage is actually a farm, where they are raised like cattle for their meat. The creatures also reveal that the intelligent students are classified as good meat which is why the children’s education is a main priority in the orphanage. To add to the duo’s surprise, Isabella arrives at the scene and starts talking to the demons about the brightest students she has.
After the revelation, Norman and Emma somehow manage to escape from the place unseen and run to the orphanage. Midway, Emma breaks down into tears as she can’t believe that her entire life has been a lie. The realization hits that many of her friends who she thought were living a good life with their parents are dead and the only parental figure she knows isn’t less than a monster who kills children she raises as her own. Norman is just as shaken but he manages to keep his cool and consoles Emma.
He believes that they were bound to see the truth today because now, they can plan an escape before it is too late. However, Emma doesn’t just want to save her life. She has a strong bond with everyone in the orphanage and can’t stand the thought of them being betrayed and killed. To her, one thing is sure, if she is escaping from the place, so are all her loved ones.
The next day, Emma and Norman are discussing the events that transpired the previous day. While Emma is worried about her fellows, Norman is adamant that they should plan a secret escape and come back for the others later.
As the first step to their plan, the duo decides to cross the forbidden fence to take a look at the outside world. However, when they reach there, they come across an extremely tall wall. Since the kids have no equipment to scale it, they decide to return back and think of an alternative. Later on, one of the children named Naila gets lost in the forest. Everyone panics but a calm Isabella uses a watch to locate and retrieve the little girl in no time. Norman and Emma observe the incident carefully and realize that the watch is used as a tracker to monitor everyone’s location. This makes their job harder because even if they get out of the orphanage premises, it wouldn’t take Isabella long to figure out where they are.
The very next day, the duo returns to the woods with a rope, so they can finally scale the wall. As they are discussing their plan, their best friend Ray approaches them and inquiries about what they are doing. As a result, Norman is compelled to reveal the truth but surprisingly, Ray believes it immediately and also suggests they run away from the place as soon as possible.
Later that night, a new caretaker named Krone is introduced to everyone by Isabella. She is supposed to be with the kids all the time even when Isabella isn’t around, and so, her arrival makes it even tougher for the group to escape. That day, as Isabella and Krone are chatting, Isabella reveals yet another shocking truth; she is aware that Emma, Ray and Norman know about the orphanage’s true motive. Despite this, she is confident in her work and won’t confront them as she knows they can’t and won’t escape. In the next scene, the trio discusses their escape plan in private. Norman believes that there is a spy among the children, who discloses everything to Isabella. If this is true, they know that the spy is one of the older children. In the following scene, the group decides to tell two of the older children, Don and Gilda, about the reality of the orphanage. They don’t believe the kids at first but eventually agree to help them.
Later, when the trio is alone, Norman says that he told Don and Gilda two different locations of the ropes that they are about to use to climb the wall. The plan is simple, the rope that will disappear first will reveal who the spy is. The next day, one of the ropes disappears. Emma and Ray are happy that they found the spy.
But Norman instead reveals that the rope story was a trap for Ray and not for Don and Gilda. He had his doubts about Ray so he gave him a fake location to find out if he was the spy, and Ray fell right into the trap. Seeing that there is no way out, Ray eventually admits to his doings and discloses that he discovered the orphanage’s motive a long time back but also found out that there is no way to escape. He even confronted Isabella about it but the woman didn’t even give him the time of the day. She is confident in the system she created and isn’t afraid to deny that no matter what, all the children must be sacrificed one day.
Hence, Ray made a pact with her and started working as a spy for her in order to delay his ‘adoption’. He promises that he hasn’t disclosed to Isabella about the children’s plan to climb the wall, which makes Norman believe Ray isn’t loyal to her after all. In addition, Ray also reveals that he has been planning to escape for a long time while the other kids were oblivious of the truth. As a matter of fact, he was the one who stole Conny’s toy so that Emma and Norman could run after her and find out the truth and would try running away too. After listening to the entire truth, Norman is convinced and decides to keep Ray in the team as a double spy.
Later that night, Ray approaches Isabella and falsely reports that Norman has been trying to poison her food. Isabella thanks him but also informs him that his adoption day is near.
The next day, as the children are planning to jump over the wall, Krone catches them red handed. Surprisingly, she doesn’t report it to Isabella but rather joins them. It turns out that a long time ago, Krone was also a student like them but her motive isn’t the same as theirs. She wants to remove Isabella and be the new mother of the orphanage, and for that, she is ready to help the kids.
At night, they go to her room, where Krone tells them everything she knows about the outside world. This is where we find out that a millennium ago, humans and demons were at a full fledged war.
After going hammer and tongs at each other for a long time, the two sets of opponents eventually grew tired and decided to stop the war. An agreement called “The Promise” was made, according to which both humans and demons would live in their own separate worlds. Each side kept their end of the deal but sadly, some humans were stranded in the demon world, and this is how the human breeding farms came into existence. Eating human meat helps the demons gain human-like attributes, preventing them from turning into barbaric creatures. The humans also agreed to this, hence they sacrificed a small number of their own people for the sake of peace.
The next day, Isabella somehow finds out about Krone’s intentions and fires her immediately. On her way out, Krone sees their supervisor grandmother at the gate. In a surprising turn of events, the grandmother makes a demon eat Krone for trying to help the kids. Elsewhere, the kids don’t let Krone’s disappearance hinder their motive and initiate their plan. Emma and Norman go to the wall while Ray stalls Isabella and the other two keep an eye on her. To their dismay, it doesn’t take Isabella too long to find out what is going on and this time, she isn’t happy about the children’s shenanigans. She easily tricks Ray and locks him inside a room before making her way to catch Norman and Emma red-handed.
On finally confronting the duo at the wall, Isabella lashes out at them. In her defense, she has given everything to the children as their own mother would and they are disrespecting her by trying to resist the inevitable. Emma, who has had enough of lying and deceiving, attacks Isabella in a fit of rage. But it goes to waste as she is easily overpowered and has her leg broken. Isabella then informs Norman that he has been adopted, and the next day will be his last at the orphanage.
The commotion ends and everyone returns to the orphanage but the group of children don’t want to go down without a fight. They reunite at night to plan their escape and are especially worried about Norman. He, on the other hand, confidently claims that he would happily die if that meant everyone else in the orphanage is safe. When everyone eventually falls asleep, Norman finds a strange pen in his drawer.
It was kept there by Krone to help them escape when needed. The next day, Norman yet again goes to the wall and climbs on it with the help of a rope, only to come across a cliff that he can’t cross.
Sensing the inevitable, he returns back to the orphanage and accepts his fate. His friends hug him for one last time and send him off with tears in their eyes, helpless that they can’t save him. Soon, Isabella escorts him away, as Emma cries uncontrollably, mourning the death of her best friend. Outside the gate, Norman is surprised when he comes across a man instead of a demon. The man then claims that he oversees if everything goes well in the world of demons and humans. Before he can explain the reason for his visit, a demon approaches Norman, ready to feast on him.
The movie then abruptly cuts to a few months later when Emma is still recovering from her leg injury. As it turns out, the group has forgotten about their plan to escape and accepted that getting eaten by the demons is their fate. Isabella, who observes them everyday, couldn’t be any happier about the situation. With the children going back to their obedient selves, her job is easier and better.
As weeks pass, the day finally comes when Ray has to be sacrificed to the demons. Emma feels helpless but she doesn’t want to lose yet another friend to the horrible system. The night before, she comes to visit Ray and tells him that they still have a chance. But a distraught Ray, in the heat of the moment, has decided to end it all. He lights himself on fire along with the building, claiming that if the entire place burns down no more children will be brought here to be sacrificed.
As the fire starts to spread, Emma panics as she doesn’t want the children to get hurt. She lets out a loud cry and calls for Isabella. A while later, Isabella arrives and quickly tells the kids to run away from the building before she tries to extinguish the fire. It takes her a few minutes before she suddenly realizes that there are no kids around.
This is when she gets to know that this had been the children’s plan all along. In the past two months, while Isabella was busy keeping a close eye on Emma, Don and Gilda informed the other kids about the escape plan. Emma didn’t interact with anyone and pretended to be depressed to trick Isabella into thinking they had given up.
In addition to all this, months ago, Emma also found a letter in Norman’s bed that had an elaborate plan written on it. In the letter she explained that she had to run away without the kids because she couldn’t put their lives in danger. However, she has promised to come back for them when they have more help.
In the present, the group scales the wall as Isabella runs towards them, looking for their precise location with the help of her navigator. However, she ends up at a random part of the forest before figuring out her navigator is malfunctioning. We find out that the navigator uses a device embedded behind the children’s ears to find where they are and over the course of the past three months all the children had taken their devices out.
In a fast paced climatic scene, all of the children reach the top of the wall. They have brought with them a cable which they use to slide through to the other end. One after another, each child reaches their destination but when it is finally Emma’s turn in the end, Isabella finds them. Seeing her children slipping away from her hands, she grows frantic and threatens to cut the rope. For what seems like an hour, Emma looks into Isabella’s eyes, almost encouraging her to cut the rope. But she knows that no matter what, Isabella can never hurt her children.
Emma then finally hangs onto the rope and slides to the other side. Isabella has enough time to cut the rope and ruin their plan but she doesn’t do it. In contrast, she has a slight smile on her face as she looks at them, almost as if she is proud that the children she raised grew up to be so brave.
However, the escape doesn’t end there as the children are in a jungle with no idea of the outside world and nowhere to go. After reaching a seemingly safe spot, they come to a halt. Emma then shows them the magical pen Krone had left behind for them.
As she opens it, the pen projects a visual of a magical owl. The owl then leads them through the woods to a nearby city, where they will be safe.
Elsewhere, Isabella is summoned in front of the grandmother and the overseer of both worlds. They are disappointed in her for letting the valuable children slip away from them, but Isabella shows no regret or remorse. she is fed to a demon as punishment and gets her karma by facing the same horrific death she put her children through.