In the near future, an unspecified apocalyptic event wipes off the human population on a Tuesday
afternoon. It is so sudden in fact that people die right there where they sit. In a little American
town, Del believes to be the last man on Earth and has created a peaceful routine for this lonely
life of his. He lives in the library where he used to work and still keeps good care of the books,
organizing them all neatly so they can be preserved. When it comes to food, he takes
things from supermarkets but also has taken up the hobby of fishing, since unlike mammals fish are
still alive and well. Del also has a whole system in place to visit the houses in town. Every day
he chooses a house and cleans it while keeping his face protected, taking every picture he may
find inside, every useful item like batteries and gas for his truck, and takes all the books to his
library. If he finds any bodies, he wraps them up in their own sheets and then buries them with the
help of an excavator. Once he is done, he adds an X in front of the house, then marks it on his map
too. One night, Del goes to bed after watching an old movie as usual when suddenly he is shocked to
hear an explosion outside: fireworks are glowing in the sky, meaning someone else is around.
The next morning, he goes to town to investigate and finds a car that has crashed because the
unconscious driver Grace had been drinking. A quick look inside the car also shows she
was the one behind the fireworks, and she has got a gun with her. Moments later, Grace wakes
up inside a random house with a bandage on her head. After throwing up, she tries to open the
door only to find it locked; Del is on the other side asking questions. Grace explains she has
not seen anybody else and that she does not know why she is alive, which matches Del's experience;
the gun she found on the road and only kept for safety. Del does not want her to stay and has
prepared a car for her, so he will open the door only if she promises to come out after
counting to one hundred. However Grace breaks her word and opens the door immediately, causing Del
to rush out of the house. After giving her the keys, he goes away ignoring anything she has to
say and her wish to stay. Grace does not give up though and she begins following Del around,
offering her help with the cleaning. With two pairs of hands they may finish faster and move on
to the next town, but in Del's eyes, there are no other towns. He does not accept her as his helper,
but Grace continues to follow him anyway, bringing a bright presence and noise into his life that had
been missing for a long time. And while Del does share his food with her, he makes her eat at a
different table and refuses to chitchat or discuss theories behind what caused the apocalypse, until
one evening he shuts Grace up by pointing out he had already been lonely when he was surrounded by
the townspeople. Seeing as she is not making any progress, Grace picks up her things and gets ready
to leave, but as soon as she gets in a car, Del comes and admits he has changed his mind so she
can stay for a trial period. From then on, Grace goes with Del to clean houses and gets to learn
his process. That is also how she realizes Del knows the name of all the bodies in town and still
remembers if they owe him any books or late fees. When the time comes to bury the dead, Grace finds
it very cold of Del not to say anything in memory of the poor people and shares the fact that every
time she found a body on the road, she would hold her breath for ten seconds. Just to humor her,
Del begins doing it with her. Del sometimes still says he misses the quiet, especially when Grace
will not shut up while they go out for groceries or she plays music really loud in the truck,
but he does not push. One afternoon, Grace notices Del is not in the library and takes the chance to
look around his office, where she is shocked to find a whole organization system in files for the
pictures from the houses. It is rather creepy and Grace does not know what to think of it,
so she goes out for a bicycle ride to clear her mind. Suddenly she hears a noise coming from a
house and when she goes inside, Grace is surprised to find a dog that has somehow survived too. She
takes it to the library to keep as a pet, and while Del is not amused by this turn of events,
he still offers some ideas for names, although in the end they still call it Dog. Little by little,
Del and Grace are becoming more fond of each other, they begin eating at the same table and
Grace shares some stories of her childhood, like the fact she used to own two goldfish. However she
still does not dare to put her hair up because she does not want Del to see a mysterious scar on the
back of her neck. A few days later, they find Dog in the middle of destroying a book. Frustrated,
Del tells Grace to clean while he takes the animal outside, but when he tries to do so,
Dog bites him. Grace helps Del clean the wound and stitches it up, but now Del is incredibly
annoyed by the dog's presence, and the fact Grace showers it with affection does not help.
The next morning, Grace wakes up to find the dog gone. She does not understand how it happened
since she had tied Dog up, and while looking for it around town, Del admits he let the dog out to
pee. It sounds like an excuse to cover the fact he got rid of it and Grace gets furious, so when they
return to the library, she gets drunk and brings out the files with the pictures. While accusing
Del of thinking people like objects, Grace reminds him that while he had been bitter and alone in his
old life, she had been happy and lost it all. Del goes to bed with heavy guilt on his shoulders,
so the following day he introduces Grace to his secret greenhouse and gives her permission
to take care of the plants as an apology. He also indirectly calls the trial period over by allowing
her to clean houses on her own, that way they will cover more ground faster. A new routine starts of
them working together as equals and Grace begins helping with the meal preparation as well,
yet she still keeps her scar hidden. She also finds a pair of walkie-talkies in a random house,
which will allow them to stay connected even when they are apart. One afternoon, Grace finds
a house that is not on the map, but as soon as she enters it, a furious Del comes after her to
tell her she should not be there. He does not want to clean this house, and that is how Grace
realizes this is Del's old home. When she points it out, Del tells her of the first deaths he saw,
which had been little kids in recess, then finally gives in and accepts to clean the house with her
help. Burying his own mother is emotionally harder than taking random bodies, and this time Del takes
more than ten seconds to hold his breath as a goodbye. Once they are done with Del's family
home, Grace finally admits there is something she has not told him, but instead of just saying it,
she kisses Del to put him to sleep. When Del wakes up the next morning, he finds himself on the bed
of the same house he had taken Grace to the first time. After grabbing the gun they left there,
Del goes downstairs and is shocked to find Grace having breakfast with two more survivors,
Violet and Patrick, who Grace calls parents even if she does not sound too convinced.
While looking strangely cheery, they explain to Del that there are thousands of survivors living
together as a community in California and Del just did not know because he never thought of
leaving his own town to seek others, otherwise he would have seen the signs they have put up on the
roads. Furious at the fact Grace has been making him feel like they were the last people on Earth,
Del rushes out of the house and ignores Grace following him while explaining those are not
her real parents. They are two adults that the community assigned to her as her new parents,
they were not originally married either, and she thinks they are freaking crazy. Del does not care,
he pushes her away and drives back to the library, where he throws up all his pain. Meanwhile,
Violet asks Grace to come back to California with them because she can not do this alone anymore
and they need to become a real family. Before the trio leaves, Patrick visits Del at the library to
invite him to come to California with them, since his skills would be very well received. There is a
team of doctors that has come up with new ways to harness the complexities of the human mind,
but since this speech does not impress Del either, Patrick leaves after writing the address on a
random book in case Del ever changes his mind. Moments later, Grace leaves the town with Violet
and Patrick, crying her heart out as she looks at her new parents' neck scars and remembers what is
waiting for her in California. Del tries to go back to his old routine but now the loneliness
and the silence are enough to get on his nerves, and he ends up channeling his frustration by
throwing things at his old house. After a night spent dreaming of Grace playing old movies in
the library, Del decides to take out all the files with the pictures to describe what he
sees. He remembers every face and their names, but also their occupations, their personalities,
and their reading taste. As he realizes he was never truly alone and this lifestyle does not
suit him anymore, Del desperately searches the library for the address Patrick left without
being careful with the books for once. The trip to California is long and arduous, but Del is a
survivor and has brought plenty of supplies with him. Whenever he finds a road blocked by other
cars or he runs out of gas, he simply changes into a different abandoned vehicle and keeps
going. Once he finally makes it to California, it is quite overwhelming for Dale to see the glowing
lights of a working city, but he pushes through his antisocial tendencies until he finds Grace's
home. Patrick and Violet are around, so Del waits until night falls and everyone goes to bed before
grabbing the gun and breaking into the house. It does not take him long to find Grace's room
and the sight that awaits him is quite disturbing: she is connected to a machine that is putting her
through behavior modification to forget about all the trauma caused by the apocalypse and the loss
of her family. In fact, every person in this community has gone through the same treatment,
since it is the only way they can move on and be happy again. Del wastes no time and apologizes
for his attitude before helping disconnect Grace from the machine, luckily she is healthy enough
to stand up and leave with him. On their way out they bump into Patrick, who tries to stop them
and explain their system is the best option, but Grace grabs the gun and shoots him on the spot.
At that moment, Violet shows up and mentions she used to have a daughter only to then continue with
the same forced-chill attitude as usual, meaning she goes looking for something to clean up the
blood as if a body was just spilled milk. After picking up some supplies and Grace's goldfish,
she and Del leave the town while ignoring the people on the streets living their lives with
manufactured happiness. Once they reach the road, Grace admits she is not sorry she shot Patrick,
and Del assures her that is fine while picking up speed to reach their next destination.