A 70-mile-wide asteroid called Matilda is approaching Earth, so all the world’s governments send a spaceship to try to destroy it. Unfortunately the spaceship explodes as soon as it enters the asteroid field, which means humanity is doomed. In three weeks the asteroid will hit Earth and all life will end.
Married couple Dodge and Linda hear the news on their car radio, however Dodge doesn’t react, he just mentions they missed their exit. Linda can’t take his attitude anymore and abandons him for good. Afterward people all over the planet start making end-of-the-world plans, especially going through their bucket lists.
Signs appear on the street offering services like naughty meetings, searching for friends to spend the end together, and mercenaries even offer to kill whoever isn’t strong enough to make it to the last day. However Dodge doesn’t have anything in life, so he continues to go through his boring routine. With twenty-one days left, Dodge still goes to the gym, which is mostly empty.
On the TV he watches a news update informing that all cellphone services are dead and that water and power will follow soon. Then Dodge drives to work and has to deal with worse traffic than usual because everyone is trying to escape the city to go somewhere nice. At the office, Dodge notices only a few workers have come today.
He keeps on picking up calls from clients who want to know if there’s insurance for worldwide catastrophes and attends meetings that announce there are promotions available for everyone because of all the people who aren’t coming anymore. However nobody from their little group takes the offer. When Dodge goes home, he checks his mailbox but it’s empty as usual.
He also notices his neighbour Penny run out of her apartment after breaking up with her boyfriend Owen, who is yelling at her. Then Dodge enters his apartment and finds his weekly cleaner Elsa. Dodge tries telling her that isn’t necessary for her to come again because of the current situation, but Elsa gets upset because she thinks he’s firing her, so he takes it back and she says goodbye while promising to return next week.
Then Dodge drinks cough syrup and watches TV, learning that the final flight has taken off and now airlines aren’t working anymore. People with private planes can fly if they want, but experts don’t recommend it because of the risks. Before going to bed, Dodge finds a spider in the bathroom and gets ready to kill it, but in the end he decides to let it live.
That night, the spider walks all over his face. The next morning, Dodge wakes up with multiple spider bites on his face. When he arrives at work, the body of a coworker who just self-deleted lands on his car, leaving him shaken.
A week passes and with only fourteen days left, Dodge goes to an end-of-the-world party thrown by his friend Diane. She has a teenage boy who insults his parents before leaving and they just insult him back, not caring anymore. Her husband is finally taking out his very exclusive cigarettes and promises to share one with Dodge while Diane comments that she isn’t surprised that Linda left him because she was never happy with him.
This leaves Dodge in shock because he honestly never noticed. Diane insists on setting Dodge up with someone because he shouldn’t die alone, and when Dodge refuses, her husband points out he won’t die alone because the whole world is dying together. When the party begins, Diane still introduces Dodge to Karen, who has put on all the fancy things she rarely got to wear.
She tries to make conversation with him, but it’s very awkward and Dodge doesn’t know what to say. During dinner, people share their plans for their last days, like visiting their family or doing things from their bucket lists. Karen says she wants to spend them with someone special while making flirty faces at Dodge.
After dinner is over, the party truly begins and gets so wild that people are even allowing the children to drink. Karen dances while still flirting with Dodge, who tries his best to ignore her. A friend tells Dodge that because of the incoming end, women have no standards and every man has a chance no matter how ugly they are.
He reveals he was intimate with tons of women last week, and asks Dodge to team up with him to sandwich Karen, but Dodge turns him down. Soon the fireworks and illegal uppers come out and Dodge can’t take it anymore, so he hides in the bathroom. When Diane comes to check on him, she shocks him by trying to kiss him.
Dodge immediately turns her down and reminds her that she’s married, but Diane explains nobody cares about that anymore. Tired, Dodge decides to go home early and think about his old life. While looking at a picture of his high school sweetheart Olivia, he starts to play the harmonica, only to stop when he hears a woman crying on the fire escape.
Dodge checks on her and discovers it’s Penny, who immediately hugs him as she cries her lungs out. She missed the last flight to the U. K.
, and now she won’t be able to be with her family during the end. Feeling bad, Dodge invites her in and shares his cough syrup, which has been mixed with vodka. In return Penny offers some pot, which he turns down.
Penny explains smoking is the only thing that helps her both sleep and wake up because she suffers from hypersomnia, which means she can sleep through everything even the apocalypse. Then the duo watches TV together and falls asleep on the couch. The next day, Penny continues to sleep no matter how loud the TV is or if Elsa is vacuuming right next to her.
Dodge pinches her nose and nothing happens, so he plays the harmonica instead. This finally wakes her up and she announces she’s finally ready to go to her apartment. They go downstairs and Penny brings Dodge a pile of mail, explaining that the mailman always sent Dodge’s things to her mailbox by mistake.
This has been happening for years and she’s been saving it all, but she never saw him around to give it to him. The only person she knew is Linda, who Penny thinks was Dodge’s roommate because she always saw her very happy with a boyfriend. Dodge is shocked to realize Linda had been cheating on him, so he goes back to his apartment and furiously destroys all of Linda’s belongings, feeling like a complete idiot.
Then he buys a bottle of blue liquid and goes to the park, where he sees a couple of teenagers kissing and yells to scare them away before drinking until he passes out. His plan to self-delete fails and he wakes up perfectly healthy the next morning, only to find an abandoned dog tied to him and a note that says "sorry". With only twelve days left, Dodge takes the dog and starts making his way home.
As he walks through the city, he notices people have finally gotten violent, meaning there are fights, fires, and looting everywhere. Later at his apartment, Dodge feeds the dog and watches the news, learning that riots are happening in many areas. He also starts going through his old mail and is shocked to find a letter from Olivia from months ago.
She explains she never stopped thinking about him and wanted to check on him, but she also tells him not to find her because it’s too late for them. Her last line says he was the love of her life. Suddenly a brick breaks through his window and the alarms in the building go off as the riots come closer.
There already are violent people in the hallway, so Dodge takes the dog, the harmonica, and the letter before going out through the fire escape. He goes to Penny’s apartment and meets Owen, who assumes Penny has been cheating with him and punches the wall, breaking his hand. Dodge ignores him and goes to wake up Penny, only for Owen to immediately start arguing with her.
When Dodge finally gets to mention the riots, Penny stops to grab as many records from her collection as possible. Then the trio runs out of the building and Penny volunteers to drive, but she’s forgotten where she left her car. At that moment some people open fire, so Owen uses Penny as a shield to protect himself.
When they finally find her car, Penny has trouble driving away because she isn’t very good at parallel parking. Owen leaves the car to guide her, however he keeps insulting her, making it clear why she broke up with him. Tired of dealing with the couple’s arguments, Dodge tells Penny he knows someone with a plane and he’ll introduce that person to Penny if she takes him out of there.
Motivated, Penny finally takes the car out and drives away, leaving Owen behind. Unfortunately the next day they already run out of gas because Penny didn’t fill up the tank. As they walk down the road, Penny tries to stay positive, causing Dodge to finally snap.
He tells her she ruined his life because he didn’t get Olivia’s letter in time, and who knows where she may be now. Feeling incredibly guilty, Penny promises to reunite Dodge with his lost love. Then Penny starts hitchhiking and a man Glen agrees to give them a ride.
As they travel together, Penny tells Glen to share his life story, and he starts from his dad’s childhood. Dodge hates every second of it, especially when Glen confesses doctor had told him he only had six weeks to live right before the end of the world was announced. Glen lost his love a few years ago and after learning about the end he started considering self-deleting, but that wouldn’t get him into heaven.
His tone makes Dodge very suspicious, especially when he sees digging equipment in the back of the truck. Eventually Glen stops the truck and says he’ll go relieve himself, inviting Dodge to come along. Getting more suspicious, Dodge turns him down and as soon as Glen is gone, he tells Penny they may be traveling with a psycho.
Penny doesn’t take him seriously and leaves the truck to walk the dog, who also needs to pee. Then Glen comes back and asks Dodge to drop the mask, saying Dodge’s blank face proves he’s a killer. Dodge denies such a theory and Glen apologizes for the misunderstanding, explaining he hired a mercenary to end things for him.
As he laughs, Glen suddenly is shot, and Dodge sees the mercenary drive away. Afterward Dodge and Penny bury Glen’s body with his own equipment and leave in his truck. Eventually they find a restaurant called Friendsy's by the road and decide to stop for a drink.
The waiter receives them with hugs and confesses all the workers have been smoking, so now they’re making up all kinds of crazy recipes. Penny and Dodge stick to the classics, getting some food for the dog too, and Penny even joins the conga line. While they eat, they share more about their old lives, but they’re suddenly interrupted with a surprise: Penny told the waiters that it’s Dodge’s birthday so they bring over a little cake and a song.
Suddenly a waitress kisses both of them and soon the party starts getting naughty, so the duo takes the dog and leave. In the truck, they notice a certain tension between them and end up doing the dirty together. Later Dodge feels guilty because of their age difference makes him feel like he took advantage, but Penny reminds him she’s an adult who made a choice.
Suddenly they hear sirens and are shocked to see a cop trying to pull them over. Penny wants to keep on driving because the law doesn’t matter anymore, but Dodge doesn’t want trouble and forces her to stop. Since she’s smoking, Dodge takes her cigarette and hides it in his mouth, only to accidentally inhale some smoke.
The cop comes over and lists all the things they’re doing wrong, so Penny points out it's pointless. However the cop doesn’t care and arrests them anyway. In jail, the duo finds a guy who was arrested for disturbing the peace with his “the end is here” sign.
Penny has a breakdown because she’s failing her promise, so Dodge hugs her through the bars and explains she didn’t ruin his life because he already did that to himself a long time ago. As the cigarette finally starts kicking in, Dodge admits he has no family: his mother died of a terrible illness and his father left them. Then he plays the harmonica until they fall asleep.
The next morning, a new cop arrives to take on his shift and immediately releases everyone. Unfortunately he can’t return the truck because it got impounded, but he does offer a ride. Penny remembers an ex lives nearby so the cop drives them there.
Dodge immediately gets jealous when he meets Speck, a former military man with a great body and his own bomb shelter, crowded with other military buddies. He’s obviously still in love with Penny and offers her his satellite phone so Penny can finally call her family. She cries when she finally hears her parent’s and siblings’ voices and even gets to listen to her baby niece for the first time.
While she’s busty, Speck tells Dodge that only Penny is allowed to stay in the shelter, not him. Afterward Penny asks Speck to lend her a car, refusing to stay. Speck agrees to do so but tells Penny to bring it back after she’s done with her promise to Dodge.
The duo continues to bond during their trip and eventually they make it to Olivia’s childhood home, but nobody answers the door. Penny breaks the window to open the door and they find lots of food in the fridge, so they agree to spend the night there. Dodge finds a record player and Penny gets to listen to her old records while she cooks.
When Dodge wakes up from a nap, he shares dinner with Penny and the dog, and Penny tells him more about her family, including the love for records she got from her dad. Then Penny checks a drawer and finds a letter from Olivia to her parents, which includes a return address. Dodge gets excited and they agree to go there the next day.
That night, Dodge discovers Olivia wrote his name on her childhood bed, and Penny smiles at the old pictures of Dodge from an old yearbook. The next morning, they go to the address on the envelope and Dodge tells Penny to wait in the car. He goes to the house only to come back a few seconds later and drive away.
Penny is confused as Dodge explains he didn’t knock, he just left a letter. An argument ensues when Penny demands to know what has changed, causing Dodge to almost crash against a line of people. The duo leaves the car and follows the line to the local beach, where people are getting baptized.
Finding the sight rather sweet, Dodge and Penny share a kiss and join the people on the beach, spending the day on a lovely picnic and befriending everyone. The dog gets to play with the locals as well. Dodge tries to teach Penny how to play the harmonica and she discovers it was a gift from his dad.
Then the duo keeps on travelling and arrives at a house in the countryside. The guy with a plane is Frank, who happens to be Dodge’s dad. Penny gives them some privacy and Frank tries to apologize to Dodge, who explains it doesn’t matter anymore since the end is coming.
However Frank still tries to be nice and the three of them spend a lovely dinner together, to the point where father and son play the harmonica together. Once Penny falls asleep, Dodge carries her to the plane and tells her she’s the love of his life before Frank flies off to the U. K.
Afterward Dodge goes home with the dog. He finds a note from Karen and Elsa cleaning his apartment, so he finally snaps and tells her to spend the last days with her family. Elsa is hurt because she considers Dodge a friend to hang out with, so Dodge regrets it and tells her to come back next week as usual, although there won’t be a next week at all.
Sometime later, Dodge watches the final TV broadcast, during which the anchorman announces the calculations were wrong and the asteroid will arrive in sixteen hours. The anchorman also offers a very heartful goodbye speech, and the signal is finally cut. Feeling sad, Dodge goes to Penny’s apartment and begins listening to her records, remembering everything she taught him about them.
He lies down on the floor and waits for the end, listening to music until the power goes out. Suddenly the dog starts barking and Dodge is shocked to discover Penny came back. She admits she woke up during the flight and made Frank take her back.
After sharing a hug, they lie down on the bed together and confess their feelings for each other. To keep Penny awake and distracted from the explosions going off nearby, Dodge keeps talking to her and asking her questions about her old life. The couple stares into each other’s eyes as the asteroid hits Earth, ending it all.