The movie opens with a young girl named Anna nonchalantly walking along the road.
Soon after, a car pulls over next to her, and a woman asks for directions to the post office.
But then, a stranger man, along with the woman, forces her into the car.
Following this, the scene cuts to a kid, who is riding his bicycle through the same street.
He then reaches his favorite treehouse and stashes his backpack there.
Just a few meters away is the residence of the Thompsons.
The elder son, Jacob, is engrossed in playing games,
and he doesn’t even respond when his mom calls out for him, and she mentions
that Dad will be arriving home shortly with a new babysitter.
Meanwhile, Dad goes to pick up the supposed babysitter, Anna, from her place,
while the girl is waiting outside in the cold.
After the introductions, dad reveals that it’s his 13th anniversary today,
so he and his wife are heading out for dinner.
He then talks about his neighbor’s children, whom Anna has previously babysat.
He inquires about their names, but Anna strangely doesn’t seem to remember,
so she gives them some nicknames and laughs it off.
Here we get to know that the Thompsons’ usual babysitter is a girl named Maggie,
but since she is busy, she has suggested her friend, Anna to them.
Dad talks about his children, and mentions that he has 3 kids, 4 year old Christopher,
9 year Sally, and 11 year old Jacob.
Back at the Thomsons residence, the boys seem to be playfully fighting, and when they get too loud,
Mom reprimands Jacob and takes his gameboy away.
The angry Jacob then goes to his room, where his best friend, Howie,
is trying to contact him through a walkie talkie.
Howie is the same kid from the start of the movie.
Howie reveals that he has stashed something great in his treehouse,
and the two plan to meet after bedtime and have fun.
After a while, Dad and Anna finally arrive at the house.
The new babysitter meets with the younger kids and makes a good impression right away,
but the grumpy Jacob insists that he doesn’t need her help.
Meanwhile, Mom tells Anna about where the snacks are kept, the childrens’ bedtime,
and other necessary details.
Dad simply tells Anna not to let the children in the garage, and when asked why,
he reveals that his favorite Corvette vehicle is parked there.
Shortly after, the parents bid goodbye to their kids and leave for their dinner date.
As they get into their car, Anna creepily watches them from the window.
Now that the adults are gone, she is in charge of the children.
She gathers the children, and announces that they are going to play dress up.
While Christopher and Sally are happy to hear this, Jacob simply goes to his room.
Anna then tells the little kids that they can pretend to be whatever they want;
whether it be a human or an animal.
She says that pretending is a superpower which they all have within them,
and the kids are riled up by this speech.
Later on, Anna goes upstairs and tries to initiate a conversation with Jacob.
Seeing him read a comic, she asks if he has read ‘Death Vice,’ and Jacob replies that
he hasn’t, as his parents claim that it is too violent.
Anna surprisingly says that he can read it now as his parents are not here,
and she also returns his gameboy, making him happy.
The scene switches to the parents; although it is their special day, Mom is still concerned
about leaving their children with the newbabysitter, so Dad assures her that Anna is a good person,
as he has heard good things about her from the neighbors.
Back at home, the kids have put on some good costumes; Sally flaunts her beautiful outfit,
but Anna doesn’t seem to be impressed, and she even taunts the little girl.
But when she sees Christopher dressed as a dinosaur, she compliments his choice.
It is evident that she prefers him over Sally.
After a while, Jacob also arrives, resembling a motorcar racer.
The kids then gather around for a picture, during which Sally tries to pose,
but Anna rudely asks her to stop smiling.
Elsewhere, the parents finally reach the restaurant, but they are completely unaware that someone
is keeping an eye on them from outside.
At home, Anna announces that they are going to play hide and seek now.
Jacob, as always, says he doesn’t want to play, but she convinces him to give it a try.
She then asks him to count till a hundred, while the rest of them will hide.
But as soon as Jacob closes his eyes, Anna starts exhibiting odd behavior.
At first, she turns off the wifi router, then, she removes all the laces from the kid’s shoes.
She even enters the dad’s garage, and checks on all the tools,
and then breaks open a safe in the parents’ room.
Later, when Jacob comes upstairs to look for everyone, she calls him in the bathroom.
She mentions that she’s on her periods, and asks the confused boy to bring her some tampons.
The little boy complies, but it is evident that he is very uncomfortable.
What Anna does next is quite shocking; she uses the tampon right in front of Jacob, disregarding his age.
In the next scene, she gathers the kids for a night meal, but even this time, she is rude towards Sally.
She lets the boys have as many cookies as they want, but the little girl gets nothing.
Looking the disgusting manners of Jacob, Anna punishes him by ordering him to eat the full
packet of the cookies.
He requests some milk, but she refuses to give it unless he’s done eating the cookies.
Following this, Anna even allows the kids to make paintings on the wall, while she goes
to the parents’ room, and starts trying some of mom’s jewelry.
When she comes down, Jacob has already drawn her name on the wall to catch her eye,
but she praises only Christopher’s painting, even though the other kids have made some
excellent artwork.
Jacob then asks Anna to help him feed his pet python, and mentions that only the two
of them should go as it is dangerous for the little kids.
However, Anna, who is an evil bitch, disregards his advice and decides to take all the kids there.
Moments later, Jacob brings a dead rat to feed the python.
But Anna thinks that it’s not enough for such a large reptile.
She instead brings out Sally’s pet hamster, frightening the girl.
A struggle ensues between the two, and the hamster’s box ends up falling on the ground.
Unfortunately, the naive Christopher picks it up, and drops the hamster right into the python’s enclosure.
Sally freaks out, and she pleads with her brother to get her hamster out.
Seeing this, Jacob tries to help, but Anna stops him, and she also forces Sally to watch
her pet being eaten, which causes Sally to burst into tears.
It is at this point that Jacob realizes something’s wrong with this woman.
At the restaurant, the parents are having a wonderful time; they give each other gifts
and talk about their future plans, while the unnamed guy is still observing them from outside.
Back at home, Anna calls the kids to the living room, saying it's movie time.
Sally, who is still shattered by the loss of her pet hamster, doesn’t want to go,
but her little brother convinces her to forget about it.
Just before the movie begins, Jacob excuses himself and goes upstairs.
It is revealed that he goes through Anna’s belongings, and finds a bullet.
He also shockingly discovers that the new babysitter in the house right now is not Anna,
but someone named Emelie.
Downstairs, the evil woman does something unimaginable.
Instead of playing a kid’s movie, she puts on an erotic tape that the parents have made.
Christopher, who is too young to understand, is amused, but Sally covers her eyes in disgust.
Shortly after, Jacob arrives at the scene, and as soon as he watches the footage,
he turns off the television.
He smashes the remote control on the ground, saying the video is private.
Emelie then says it’s time for bed; she takes Christopher to his room,
and begins reading him a bedtime story.
Using a weird looking drawing book, she narrates that once upon a time,
there used to be a momma bear who loved her cubbie a lot.
Everyday when she came home from work, she was very happy to see him,
as he made her forget all of her problems.
But one day, Mama bear made a mistake, and the cubby died.
We also see flashbacks of her past, revealing that she is talking about herself.
She had accidentally slept on top of the baby, causing it to suffocate.
Outside, Jacob and Sally are listening in on the story as well.
Emelie mentions that Mama bear was broken after the death of her cubby.
Her mind cracked, and this is when she met Skinny Hyena, whose mind was cracked more
than that of Mama bear.
He promised to give her another cubbie, but Mama bear’s body isn’t capable of producing
any more children, and she was unable to adopt a new child due to eligibility requirements.
As a result, Mama Bear and Skinny Hyena were overwhelmed, got into some trouble,
and ultimately had to leave town.
But now, they are on the search for another cubby.
Here, it is revealed that the man who is keeping an eye on the parents is actually her husband.
The two have just arrived in this country, and they are looking to kidnap a child.
The target is obvious, Christopher, and they already kidnapped the real Anna at the start of the movie.
As bedtime approaches, the kids get into their PJs, but Sally finds the safe box
in her parents’ room, which Emelie had opened.
There is a gun inside, which Jacob grabs.
He then tells his sister that the woman who has been babysitting them is actually an imposter.
Unfortunately, Emelie hears this and confronts the children, so Jacob points the gun at her.
He warns her to stay away, but Emelie confidently asks him to shoot.
When Christopher suddenly arrives, Jacob quickly hides the gun.
However, the little boy finds the gun and aims it at them.
The little boy thinks it’s a toy, but it turns out the gun is not loaded.
Anna takes the gun away, creepily calling herself a mother.
Just then, the doorbell rings, but Emelie quickly locks them in a room,
and warns them to be silent.
She even slaps Jacob to make a point.
The woman then goes downstairs, and surprisingly finds the Thompson’s regular babysitter,
Maggie, outside.
The latter checks in at the front door, since she hasn't heard from Anna, her friend.
In response, Emelie lies that Anna suffered food poisoning,
because of which she had to be replaced.
Maggie buys the story and simply asks to see the kids before leaving.
The evil woman initially refuses, but finally obliges as she doesn’t want to arouse any suspicion,
while we can see Jacob write something on paper.
Emelie then goes upstairs, and warns the children not to do anything drastic,
or else she will kill Maggie.
Following this, all of them go downstairs, and meet Maggie.
The latter senses that the children are unusually quiet, but she doesn’t say anything at the moment.
Before leaving, Sally hugs her tightly, but she has actually dropped a note in the woman’s purse,
and Emelie seems to notice this.
Soon after, Maggie reads the note in her car, right when this happens…
Emelie attacks her and knocks her unconscious.
She even drags the poor woman in front of the kids, and locks her in a room.
In the next scene, she forces the kids to drink the juice that has been mixed with medicine
to knock them out.
Jacob can tell what she's up to, and manages to vomit later, but his siblings are incapacitated.
Meanwhile, Mom calls Emelie to check if everything is alright.
The latter lies that she has taken good care of the children, and that they are asleep,
and the mother says that they will be back home in 20 minutes.
Realizing that they don’t have much time left, Emelie decides to initiate her plan.
At first, she cuts off the power, plunging the house into complete darkness.
Then, she grabs Christopher, and takes him upstairs.
She then decides that she wants to kill Jacob, as he is becoming a nuisance to her plans,
but soon realizes that the boy has escaped.
As a result, she calls her husband, saying she needs more time.
Meanwhile, Jacob goes to the treehouse, where his friend Howie is waiting for him with lit fireworks.
Jacob explains everything about the evil babysitter, and requests for help.
Elsewhere, the parents finally exit the restaurant, but they appear to be in a drunken state,
and decide to go home in a taxi.
The mysterious guy a.k.a. Emelie’s husband is still watching them from a distance.
Back at home, Maggie regains consciousness, and the first thing she does is attack Emelie
to save the children.
Although she puts up a good fight, she is eventually overpowered and killed.
As Emelie goes to the kitchen to clean her wounds, Jacob sneaks inside the house,
and takes Christopher away.
He then hides him in a safe location.
On the other hand, Mom and Dad are returning home in the taxi
when they suddenly get into an accident.
Luckily, the two of them survive, and it turns out that they have been hit by the same man,
who had been observing them for hours.
His goal was to buy more time for his wife so that she could kidnap Christopher,
but the man ends up dying.
Back at the house, Jacob slowly ventures into the basement to find his sister,
but he only comes across the lifeless body of Maggie, which shatters him.
As he is weeping, Emelie talks from upstairs, revealing that she has his sister.
She also throws Howie’s jacket, which has bloodstains all over it, and warns Jacob that
if he doesn’t bring Christopher to her, she will harm his sister.
She then gives him 5 minutes to come to the backyard, where the trade will take place.
At the crash site, the police inform the parents that the dead man had no ID on him,
and that he was riding a stolen vehicle.
But as soon as the police take the parents home, the cops discover a dead body in the
car’s trunk.
She is none other than the real Anna, who was abducted at the start of the movie;
she was beaten and killed by the evil couple.
When Mom and Dad learn of this news, they finally realize that the babysitter at their
home is an imposter, and they immediately rush home to save their children.
At home, Emelie is in the backyard with Sally, waiting for Jacob to show up, but the latter
knows she’ll probably kill them, so he rolls over a trash can towards her…
It turns out to be Howie’s fireworks, which burns her face.
As she drops to the floor in agony, Jacob quickly grabs his sister, and takes her away.
He then goes to the garage, and gets inside his father’s Corvette.
After loading his siblings and putting on a helmet, he opens the garage gate,
and sees Emelie is waiting for him outside with a gun.
She demands that he stop, but an unfazed Jacob steps on the accelerator, and runs her over.
He then gets on the road, and keeps driving, until he finally meets his worried parents,
and the kids reunite with them.
Mom and Dad embrace their children lovingly, promising to never leave them alone again.
As the cops surround the crime scene, it is revealed that Howie is alive,
having only suffered an injury to his head.
As for Emelie, she is shown limping away from the scene, implying she escapes,
or is presumably caught by authorities afterward.