The movie kicks off by zooming in on a middle-aged man in his bathroom.
He dyes his hair, shaves off his beard, and takes out his brown contact lenses to reveal
his natural blue eyes.
Meanwhile, scattered around his home are several pictures of him and his family.
There's a festive vibe with Christmas carols playing softly in the background.
As he moves around the house, we realize that things aren't as cheerful as they seem.
The camera shows us the lifeless bodies of
his family members – his wife and three kids – spread across the house.
Bloodied tools are visible in the kitchen sink.
Without a word, the man exits the house, and drives away with his luggage.
Cut to the next scene: we're now at the police department; detectives are huddled together,
talking about the murder case.
The prime suspect is the stepfather, a man named Grady Edwards, and he vanished right
after the tragic event.
As the police investigate, it is said that another family was murdered in a similar manner not long ago.
They believe Grady might be a serial killer, targeting single women who are either widowed
or divorced and have families.
He's cunning and doesn't leave behind any clues about who he really is.
He pays for everything with cash, so his credit card can't give him away, and no driver's
license is needed for registration on the car purchase.
It's been a while since the murder case; the guy we saw earlier, bumps into a woman in a grocery store.
When the woman's children are acting out, the man comes to their rescue, winning her heart in the process.
Her name is Susan Harding, and the man opens up about how his wife and daughter passed
away in a car accident last year.
Susan, a mom who recently went through a divorce, is clearly attracted to the man.
At the parking lot, the man introduces himself as David Harris, and uses his charming personality
to attract Susan right away.
Susan, desperate for love, invites David to a pizza party with her kids.
Of course, David agrees.
Fast forward six months; Susan's oldest son, Michael, returns home from military school
for the summer, accompanied by his girlfriend, Kelly.
Here, we learn that David and Susan are now engaged and living together with the kids,
but Michael isn't quite sure about him.
They're greeted with a surprise party - the whole family is there to welcome Michael back.
Susan warmly embraces her son, and everyone is overjoyed to have him home, and this is
when Michael finally meets his future stepfather.
David welcomes Michael back with a brief speech in front of everyone, and Michael seems to
be making an effort to appreciate David's gesture.
One of Susan's sisters, Jackie, offers David a job opportunity at the real estate company
she's working for.
Susan is happy about the idea because it means David won't have to travel so much, and David
agrees to take the job even though he is hesitant at first.
During the party, David decides to have a heart-to-heart conversation with Michael.
So, he asks Michael to join him in the basement, where David has built cabinets to store things,
some of which are locked.
Here David hopes to connect with Michael over some drinks; he's aware that Michael isn't
eager to go back to military school; he suggests an alternative - joining the high school swimming club,
so he could get a sports scholarship and eventually get into college.
After the party winds down, Michael sees his girlfriend Kelly off, while David is staring
at them from a distance.
Later, Susan visits Michael in his room.
She encourages him to give David a chance and try to get along with him, but Michael
tells his mother to hold off on the lectures for now.
The next day unfolds with David taking a trip to Michael's old high school.
He has a conversation with the sports teacher, and manages to secure a spot for Michael in
the swimming club.
This gesture means a lot to Michael, and he's really grateful.
Later on, Kelly comes over, and she and Michael enjoy some time swimming in their backyard pool.
Meanwhile, Sean is engrossed in a video game and playing it quite loudly, despite Susan's
repeated requests to lower the volume, and this is when things take a dark turn for Sean.
David also thinks that it’s not a good idea
to let Michael and Kelly be so passionate at their age, but Susan tells him not to be
so old-fashioned.
At the dinner table, Susan notices that Sean is visibly upset, and asks him if something's
bothering him, but he brushes it off.
Then, the doorbell rings, announcing the arrival of Susan's ex-husband, Jay.
Sean and Beth rush to greet him, excited for their weekend with their dad.
However, Michael is less enthusiastic, and doesn't want to spend time with him.
The following morning, there's a surprise visit from Mrs. Cutter, the neighbor.
She's seen a TV show called "America's Most Wanted," and mentions that the sketch of a
criminal featured on the show bears a striking resemblance to David.
Meeting Mrs. Cutter causes Susan to sneeze because she is allergic to cats, and Mrs.
Cutter always brings her cat with her.
When David learns what the neighbor claimed, he downplays it.
Later that day, Michael and David meet for lunch at a diner.
During their conversation about family, David accidentally calls his deceased daughter by
two different names.
Firstly, he calls his daughter Michelle, but then it switches to Lisa.
He quickly corrects himself, saying her full name was Lisa-Michelle.
This slip-up raises Michael's suspicions, and David tries to brush it off.
When David gets home, he opens Susan’s laptop and checks the America's Most Wanted website.
He is shocked to see a man and the name on the website, which is probably himself.
In the next scene, we find ourselves at Mrs. Cutter's house.
Suddenly, she hears the doorbell ring.
She goes to check, but there's no one outside.
As she heads back in, she sees her other cat who seems terrified of something,
and then out of nowhere,
David appears and shoves her down the stairs leading to the basement.
Even after this fall, Mrs. Cutter doesn't die, so David suffocates her until she passes away.
Meanwhile, Michael shares his suspicions with Kelly about David's earlier mistake in calling
his daughter two different names, but Kelly thinks Michael might be overthinking things
a bit too much.
Later, during dinner, Susan begins sneezing again and asks David if Mrs. Carter came by today;
however, David says that it's probably due to a cat from the real estate house where he works.
Soon after, Susan's ex-husband, Jay, arrives with Sean and Beth.
Jay is furious because Sean told him about the incident where David grabbed his neck
the day before, and David replies that he just wants to show him a little discipline.
Michael steps in and manages to calm Jay down, taking him outside to have a conversation.
He returns his father’s phone, and things get a little better between them when Jay
claims that he only left Susan, not his children.
During this, David is lurking on them through the window.
David then tries to mend things, apologizes to Sean, but Susan is still upset with him.
He also apologizes to Susan for his behavior, saying he just wants to get some respect,
and Susan tells him he also needs to earn trust.
In the following scene, we see that David is working with Susan's sister, Jackie, in
real estate business.
Jackie hands him a bunch of papers to fill out with his personal information.
However, David seems reluctant to do so and asks to be paid in cash instead, which the
company won't do.
When he returns home, he confesses to Susan that he's not really enjoying the real estate
job, and wants to quit.
Later that same night, Susan heads out with her sister Jackie and a friend.
Meanwhile, Sean and Michael are deep into their video games in the room.
Then, the doorbell rings.
David opens the door to find Jay standing there.
Jay has come to offer an apology to David, and spend some time with his kids before leaving
for a work trip.
Before they can have a conversation, David’s phone rings, so he goes to answer it.
Susan says Jay told him he'd be coming to say goodbye to the kids, but Jay claims he
hasn't arrived yet.
After the phone call ends, Jay reveals he did a background check on David, and he found
out that David had lied about the college he claimed to have attended.
Strangely, Jay is nowhere to be seen, and then all of a sudden…
Unfortunately, the noise doesn't reach the
boys in their game-focused zone.
Meanwhile, at a bar, Jackie expresses her worries to Susan about not knowing much about
David's past.
However, Susan takes offense to this, and asks Jackie to be supportive and happy for her.
Back at the house, David pays the taxi driver and takes all of Jay’s belongings.
He then drags Jay down to the basement, using duct tape to bind Jay's mouth and hands.
Then, he places a plastic bag over Jay's face, and suffocates him.
During this act, Michael tries to call Jay, but David immediately turns down the call.
Michael notices that the basement door is open, but he doesn't investigate further,
leaving his father to die.
Afterwards, David sends a text to Michael from Jay's phone, apologizing for not being
able to come visit, and mentioning that David seems to be who he says he is.
Michael, who believes his father no longer cares about his children, is unable to keep
his tears from falling.
David puts Jay’s bag in the locker and locks the basement before continuing with his day.
Two weeks later, the police find Mrs Cutter's body.
Michael happens to overhear a conversation between the mailman and David, and the mailman
mentions that Mrs. Cutter died in an accident.
However, David tells Susan a slightly different story; he adds details about Mrs Cutter falling
down the stairs, and this makes Michael even more suspicious of David.
While Susan's taking Sean and Beth to the dentist, David uses the moment to go up to
the attic and work on fixing its floor.
Meanwhile, Michael and his girlfriend, Kelly, are hanging out by the pool when he shares
with her his concerns about David's strange behavior that morning.
Later in the day, David heads out to pick up Sean and Beth, and this gives Michael and
Kelly an opportunity to go into David's closet to search for any evidence against him.
David is on his way when Susan calls and tells him that she will pick up Sean and Beth instead.
When they hear David come in, they quickly hide in the closet.
As David returns home, he notices their footprints and searches the house for them, but they
are nowhere to be found.
He figures out that Michael's bed isn't warm, and then he stumbles upon the moving hanger
in David's closet.
Luckily, the two manage to slip away without being noticed.
That night, after dinner, David enters Michael's room for a chat.
He tells Michael that he wants them to be honest with each other.
David seems to know that Michael and Kelly were snooping around his things.
As the night goes on, Michael slowly walks down the stairs and opens his mother’s laptop,
and that's when he discovers a browsing history that David forgot to delete.
When he looks through the website, he is surprised to find a sketch of Grady Edwards, who looks
a little like David.
The next day, Michael shows the sketch of Grady Edwards to Kelly and says it kinda looks
like David, but she still thinks it could be anybody.
Things reach a breaking point when David sends another text to Michael through Jay's phone,
so that Michael isn't suspicious of his sudden disappearance.
However, he accidentally reaches Jackie's voicemail instead, who wants to talk about David.
But then, he receives a phone call from Michael.
Michael can hear the ringing sound from inside
the vent and goes to check, only to run into David, who tells him it could be his phone.
When Michael asks where the basement key is, David says that the key is gone.
Michael then sneakily uses his phone to take a picture of David.
Later in the evening, with Susan out to drop the kids off at camp, Michael heads for a shower.
However, when he comes out, he's startled to find David standing right in front of him.
David casually inquires about Michael's plans for the evening, and Michael responds that
he'll be spending it at Kelly's place.
When he gets back to his room, he finds that the door is slightly open.
He quickly checks his phone, and realizes that the photo he took of David has mysteriously
disappeared.
Michael then visits Kelly's place, where he discusses the deleted photo, claiming that
David doesn't want his picture taken.
Back to David; he finds an email from Jackie on Susan’s laptop, discussing the idea of
hiring an investigator to look into his background.
Jackie tells Susan she'll be at the airport in 20 minutes, and David deletes the email right away.
As Jackie is getting ready to head to the airport, she notices that an umbrella
has fallen into her pool, and goes to retrieve it.
But then…
Back at the house, Susan who has just returned,
asks David if they received a phone call from Jackie, but David says he didn't.
He might be planning to kill Susan on the same night, and he gives Susan a pill to help
her sleep soundly, and we can see his tools in the bathroom.
Meanwhile, Michael and Kelly are parked outside the house in their car, and Michael hatches
a plan to sneak into the basement.
He instructs Kelly to call him if she notices any signs of activity inside.
Driven by determination, he manages to break into the basement through the skylight while
Kelly keeps watch.
Inside, he successfully breaks the locks on the cabinets, and discovers a bag with his
father's initials on it.
He finds his father's broken phone in there.
As Michael explores further, he stumbles upon a freezer.
In the meantime, David checks on Susan to see if she's slept.
Kelly then notices that the light in one of the rooms has turned on, and tries to contact Michael.
Unfortunately, his phone slips and shatters.
Michael continues to rummage through the freezer, and eventually comes across Jay's lifeless body in a plastic bag.
Kelly rushes to the skylight, hoping to communicate with Michael from there.
Unfortunately, David locates Kelly, and violently strikes her.
Michael who hears Kelly’s scream tries to get to her, but David blocks the window with
heavy objects.
He then drags Kelly to the kitchen, where he begins to gather knives and weapons.
In the midst of all the chaos, the noise reaches Susan, who wakes up and rushes to the kitchen.
There, David starts blaming Susan for her parenting and accuses Michael of being disrespectful,
claiming that this isn’t the right family for David.
He also says he thought Susan could be "Mrs. Grady Edwards," and this strange statement
leaves Susan bewildered.
David suddenly asks, "Who am I here?"
Susan reminds him of his actual name.
The mother then flees as she notices the unconscious Kelly on the floor, and hides herself in the bathroom,
locking the door.
David kicks down the door, shattering the mirror that was on it.
Susan seizes a piece of the broken mirror, and stabs David in the neck with it, causing
David to collapse onto the floor.
Meanwhile, down in the basement, Michael manages to break through the basement floor and free himself.
He joins forces with Kelly, and together they reunite with Susan in the hallway, but their
relief is short-lived, as David reappears and begins pursuing them again.
They rush to the attic for safety.
Michael attempts to shut the attic doors to keep David out,
but David manages to follow them up.
The attic's floor is weak, and during the struggle between David and Michael, a section
of the floor gives way.
Michael falls through.
Desperately, Kelly tries to threaten David with an electric saw, but the floor beneath
her also gives in.
Both Kelly and Susan fall through the broken floor.
In a final intense showdown, Michael launches an attack against David.
The confrontation takes them to the roof.
Eventually, their fight leads them to the edge, causing both of them to tumble off the
roof and land on the ground.
They both lie unconscious, and police sirens can be heard from afar.
After some time, Michael regains consciousness, only to find himself in a hospital bed.
He learns that he had been in a coma for a little over a month due to the fall.
Shockingly, David vanished before the police arrived at the scene, and he hasn't been seen since.
Before the film ends, we see David who is still alive, and has again changed his appearance.
He encounters a woman who's a widow, shopping with her two kids,
and then introduces himself…