In the middle of the desert, the car belonging to a secret agent codenamed Anacleto breaks down,
meaning the spy has to walk the rest of the way to a hidden prison where all the criminals he's
caught in his life are kept. His objective is his archnemesis Vázquez, who has been there for thirty
years and now he'll be moved to a different prison so he can spend his remaining twenty.
Anacleto's mission is to oversee the transfer and prevent any trouble, but during the trip,
Vázquez mentions Anacleto's son and implies he'll go after him for revenge, causing Anacleto to lose
his temper. Before the spy can do anything stupid though, a pair of mysterious men shoot at the van
with a bazooka and make it crash. Anacleto's body receives quite a shake and he can barely move when
the vehicle lands, so he can't do anything when the mysterious men, who turn out to
be Vázques sidekicks Butcher and Molecule, help his boss to escape. Vázquez knocks Anacleto out
before leaving, promising revenge. In the city, Anacleto's son Adolfo is working as a night guard
with his best friend Martín at an electronics store. Both of them are in their thirties but
haven't achieved anything in life, going through the same boring routine every day just to
survive. Every morning Adolfo is picked up by his girlfriend Katia, who is also Martín's sister and
works as a doctor. She never gets to play music or even share her day with her boyfriend because
Adolfo wants to sleep as soon as he enters the car, yet he also refuses to get a driving license
and save Katia the trouble of doing this chore and letting her rest too. All Adolfo does is work,
sleep, and watch tv, and Katia is tired of this boring life, not to mention the constant arguments
about driving. Finally giving up, Katia stops the car and breaks up with Adolfo, explaining she
wants a life with more adventure and excitement and that's why she's moving to India in a week.
Adolfo is left in the middle of the street and tries to call his father for help, thinking he's
at the family's old farm because he's never known Anacleto is a spy. Unfortunately Anacleto is still
in the desert and his phone is destroyed when he's found by a pair of freedom fighters that tried
to kill him, but these men aren't good enough to defeat the best spy in Spain and Anacleto quickly
knocks them out before stealing their jeep. Then, he calls his agency's headquarters to speak to The
Boss and asks for backup, but there's even more bad news for him: the agency hasn't had enough
budget for a while so they can't send a helicopter or close the borders to stop Vázquez. Anacleto
will have to return on his own, but The Boss promises to at least send two agents to keep an
eye on Adolfo. Speaking of Adolfo, in the evening he's dragged to a bar by Martín to try to cheer
him up to no avail. When they discover Katia is at that bar as well, Martín decides to confront her
about the breakup in order to defend his friend and begins an argument that ends with the siblings
fighting like they used to do as kids. A bouncer immediately notices and comes to pull them apart,
but Katia hits him where it hurts the most and runs away with Adolfo. That fight has been exactly
the kind of excitement she's been looking for, and her victory has put her in such a good mood that
she drags Adolfo to his apartment so they can spend the night together. The two agents sent
by The Boss follow the couple and park outside to keep an eye on things, but they miss the fact
they're being followed as well and they get killed as soon as they're distracted. Meanwhile Anacleto
is trying to cuddle Katia after their little fun is done, but Katia pushes him away because
this isn't a sign to get back together, she just wanted them to have a proper goodbye. Disappointed
and crying, Adolfo goes to sleep on the couch and gets to see how a burly Asian man breaks
into his apartment, but he's not a thief as Adolfo thinks, he's an assassin. A fight begins between
the two men starts and while Adolfo is scared, he unconsciously defends himself with quite a skill,
allowing him to avoid death even if he still does hit a couple of times. Both of them use
any object they find around and end up taking the fight to the bathroom, where Adolfo grabs
the assassin and smashes him through the window, killing him without meaning to. Panicking and
feeling guilty over what he just did, Adolfo goes to Katia to try to tell her to call the police,
but at that moment, a mysterious shadow knocks him out. In the morning, Adolfo wakes up in bed
with clear bruises on his face. When Katia demands an explanation, Adolfo tells her what happened but
he can't prove it because somehow the apartment is magically clean and the body is gone. Katia
doesn't believe him and thinks he made the bruises himself for pity, making her double down on their
breakup. Adolfo leaves the apartment wondering what to do next and is surprised to find his
father waiting for him in his old van. Anacleto is using his civilian cover that presents him
as a meat producer, but it was him who cleaned the apartment and hid the body in the back of
the van. He offers his son to come to lick his wounds in his old family home as a sneaky way to
keep him safe and Adolfo accepts, so they drive all the way to the countryside where their old
farmhouse still stands like the old times, even their old dog Sapristi is still around. As soon
as they arrive though, Adolfo hides in his room, refusing to spend time with his father. At least
Anacleto gets some privacy to call The Boss and confirm they're fine, but barely a few minutes
pass before he finds more assassins coming after them. The first one he finds hiding in a tree,
and a fierce battle begins using any farming tools available, including a gun Anacleto had
hidden inside his cow. Eventually they can't stop the fight from moving inside the house,
where Anacleto tries his best to keep the secret from Adolfo by hiding the assassin in the kitchen,
but Adolfo keeps coming back to look for snacks that don't have nuts in them because he's allergic
and ends up finding his father putting the assassin in the meat grinder. Seeing he has
no other choice, Anacleto finally confesses he's a secret agent, and Adolfo doesn't take it well.
He understands why he spent a lot of time alone as a kid on a boring farm now, but mostly he's
appalled at the fact his father kills people with no remorse. Their argument is suddenly interrupted
by the arrival of more of Vázquez's henchmen, who open fire outside the house. Anacleto wastes
no time and reveals his secret stash of weapons which for some reason include gum and shares it
with Adolfo, claiming he's already been trained. As flashbacks of his childhood flood his mind,
Adolfo realizes the games Anacleto put him through were actually training, explaining how he managed
to unconsciously fight the assassin that had broken into his apartment. However Adolfo still
refuses to kill and Anacleto ends up doing all the shooting himself, including throwing some gum
on the floor because it's actually a bomb. All the henchmen die without touching Anacleto or his son,
but the one that ends up activating the bomb by accident is Sapristi, who dies in the explosion.
Adolfo wants to go to the police, but Anacleto doesn't allow it and has to tie up his own son to
put him in the van, they need to leave the farm as soon as possible because it isn't safe anymore. On
their way to the city, Anacleto confesses Adolfo's late mother had been a spy too. Meanwhile Vázquez
is visited by The Boss, who wants his payment for having betrayed his best agent. When Vázquez
only gives him a couple of bucks because he has no money after thirty years in jail,
The Boss gives him twenty-four hours to get it if he doesn't want consequences. A few hours later,
Anacleto and Adolfo arrive at the spy agency headquarters, which are hidden in a post office
building. To Anacleto's shock, every single worker there is dead, apparently because of poison. They
need to go to the spot assigned in case of emergencies, but when the duo makes it back
to the parking lot, they find the assassins trying to leave. They immediately open fire on Anacleto,
who only manages to kill one guy before stealing a walkie-talkie from him and returning
to the elevator with his son. Adolfo freaks out because he notices Anacleto was hit by a bullet,
but Anacleto doesn't care and concentrates on calling Vázquez to tell him he'll get revenge
for the death of his friends. The elevator drops the duo on the roof of the building, and since
the henchmen are still coming after them, they have no choice but to jump onto a truck on the
streets. Adolfo surprises himself with a decent landing, but Anacleto is bleeding and getting old,
so he gets even more hurt. He refuses to go to the hospital because it's dangerous,
which means Adolfo has to drag him to Katia's house to ask for her help. Katia isn't sure
if believing the secret agent story but Adolfo won't leave and her parents are getting curious,
causing her to rush Adolfo and Anacleto to her room while pretending she's only with Adolfo
having a good time. This makes things awkward when Katia needs someone to help Adolfo hold Anacleto
down while she takes care of his wound and drags Martín into her room as well, making her parents
think their children may be too liberal. Sometime later, after Adolfo and Martín have fallen asleep,
Katia scolds Anacleto for having hidden his life from his own son, blaming him for making
Adolfo such a boring person by keeping him on the farm. Meanwhile Vázquez receives information about
Anacleto's location and sends Butcher and Molecule after him. The next morning, Adolfo, Katia,
and Martín wake up to discover Anacleto has made breakfast and put truth serum in the orange juice
to interrogate Katia's parents. After everyone accidentally confesses some embarrassing secrets,
the mother admits she's been selling information to Vázquez for two years and that the henchmen are
on their way to the apartment. The group sneaks out through the window using the fire escape,
and while Anacleto stays back to open fire on the enemy, Martín, Adolfo and Katia run away. Sadly
Martín isn't fast enough and is left behind, but the henchmen leave him alone anyway because they
want Adolfo and corner him inside a mall. Adolfo manages to offer a good fight with the techniques
his father taught him, but no fist can be enough to stop Molecule's taser that knocks Adolfo down
while Butcher captures Katia. The couple is taken to Vázquez's hideout, where he hurts
Kati's eye to make Adolfo confess where he agreed to meet with his father. The meeting point is the
train station, where Anacleto and Martín meet with Gimeno, an agent that works undercover as a hobo
and gets them in contact with The Boss, who is still alive. However Anacleto has played cards
with The Boss many times and recognizes his lying face, so he shoots him when he guesses he's been
working with Vázquez all along, including having given Molecule and Butcher the van route for the
prisonbreak. The reason for this is that he knew the agency would be closed soon over the lack
of budget and he wanted to create a mission big enough to show they were needed. The Boss doesn't
lie when he says he doesn't know where Adolfo is, thus Anacleto leaves him under Gimeno's watch
while he retrieves some hidden guns that he shares with Martín, who accidentally shoots his own
foot. Suddenly, civilians begin running out of the station in fear when they see the arrival of Katia
and Adolfo, who are tied together by a bomb. A kid approaches Anacleto to give him a phone sent by
Vázquez, who explains the only way to disable the bomb is to stop Adolfo's heart, touching anything
will just make it explode faster. A bomb squad is sent by the police but they can't find a solution,
so Anacleto asks everyone to leave to have a moment alone with his son. As they reminisce
about the old days together, Anacleto confesses he hasn't been this scared since his late wife had
an allergic reaction to nuts because there was nothing he could do against that unlike actual
villains he can punch. This memory gives him an idea thus Anacleto rushes to get some peanuts
from a machine and an epinephrine injection from the emergency team, the plan is to give Adolfo an
anaphylactic shock to make his heart stop, get rid of the bomb, and bring him back with the injection
and CPR. Adolfo is terrified but goes for it, and once the bomb is off, the combined efforts of
Katia and Anacleto bring him back to life safely. The mission isn't over though, Anacleto is sure
Vázquez is still in the building and he's right, he's been dressed up as part of the bomb squad.
He chases after his enemy without hesitation and Adolfo decides to go with him to help since he's
hurt, receiving a kiss from Katia for good luck. Anacleto and Adolfo find the bad guys
in the parking lot, where Vázquez tries to hide in a car while Molecule opens fire. This time,
Adolfo doesn't doubt and kills him without remorse. Butcher is coming after them too,
so Anacleto sneaks into the guard's office to grab a bunch of car keys and use the buttons
to open the doors to random vehicles from afar, effectively tricking Butcher into shooting away
from them. Unfortunately Butcher sees him anyway when he turns around and manages to land a bullet
on Anacleto, causing Adolfo to drag his father into a car and ask him to teach him to drive on
the spot. Adolfo is a terrible driver that doesn't know what he's doing, but at least this clumsiness
ends with him accidentally smashing Butcher against a wall. At that moment, Váquez shows up in
a van and drives towards them with the intent to kill so Anacleto gets off the car pretty quickly,
but Adolfo's seatbelt is stuck. Desperate to save his son, Anacleto cuts the seatbelt with a bullet
and pushes Adolfo out, getting hit by the van himself instead. Crying, Adolfo cradles his father
in his arms as Anacleto says his last words: he apologizes for the poor childhood he had to offer,
and tells Adolfo he's proud of him. Vázquez is still alive and running out of the parking lot,
thus Adolfo grabs Anacleto's gun and goes after him. He pretends to get lost in a corridor,
prompting Vázquez to approach him from behind thinking he's won, but this is all a trick to
make him step onto explosive gum. The explosion kills Vázquez but Adolfo moves away just in time.
Sometime later, Adolfo buries Anacleto on the farm with help of his friends and says goodbye to him
with heartful words. Afterward, Adolfo tells Katia that this adventure has made him understand she
was right and that he wants excitement in his life too, but she admits that for her it was
the opposite. Katia has had enough scares to last her a lifetime and now wants a quiet life at home,
this means she still doesn't want to get back together with him. Finding himself with an open
door to start a new life, Anacleto restarts the spy agency with Martín as the new boss in the
office. Taking his father's codename, Adolfo becomes the new Anacleto and fights crime,
starting by going to the desert to find the freedom fighters that attacked his dad back then.