In the opening scene, a man who turns out to be a Triad elder is killed in what appears to be an accident. However, it is revealed that the man was actually murdered, with the supposed accident actually orchestrated by a group of killers led by the Brain (Louis Koo). The group specialises in killing their victims using elaborate schemes that mask the murders as if they were accidents. Uncle (Stanley Fung), one of the team members, accidentally leaves a cigarette butt at the crime scene, and it is found by the Brain. After an argument, Uncle vows to quit smoking afterwards. The team then gets a job from a son that wants to kill his own father, likely for insurance money. They plan an accident to kill their target via electrocution, but the plan requires for it be to raining at a specific time. The team tries to execute their plan many times but fail due to the rain falling later than necessary. During one run, Uncle smokes a cigarette and begins to show signs of Alzheimer's disease, forgetting that he made a vow to stop smoking. However, the rain falls on time, and the team decides to go forth with their plan. Uncle forgets to play his part in the murder, but the murder is successfully executed nonetheless. Unexpectedly, after the murder, a bus loses control and almost runs over the Brain. The Brain manages to get out of the bus's path, but the bus then runs over Fatty (Lam Suet), another member of the team, killing him on the scene. The Brain takes Fatty's belongings, with Fatty asking the Brain whether it really was an accident before he dies. The Brain then returns home to find police officers investigating his flat, which was broken into. The Brain becomes paranoid and is convinced that everything was a setup. He trails the son to an insurance company the next day. The Brain sees the son arguing with an insurance agent (Richie Jen) over what appears to be money, leading the Brain to suspect that the insurance agent was behind the bus accident. The Brain rents a flat on the floor directly below the insurance agent's flat, and begins to perform secret surveillance on the agent. One day, the Brain trails the client to find the Woman (Michelle Ye) picking up the payment for the job at a parking garage. However, only Fatty and the Brain should have known about the pick-up. The Woman explains to the Brain that Fatty had told her about the client, but the Brain, suspecting her betrayal, kills her and takes the money. After he leaves, as he is walking on the sidewalk, the client (the son) falls from the roof of the same building and is dead. The Brain develops further suspicion of the insurance agent, who he can see talking on the phone and later hear him talking about the client on the phone in his flat. In a later date, the Brain receives a call from Uncle for help. However, the Brain is too late and finds Uncle severely injured, apparently dropping two stories from a building near the crime scene in the opening scene. The Brain decides to take revenge against the insurance agent and devises a scheme to kill the agent by reflecting the sun's rays to blind a car to run over the agent in what would appear to be an accident. However, in the middle of the plan's execution, there is a solar eclipse, blocking the sunlight. At this time, the Brain receives a call from Uncle in the hospital, who tells the Brain that Fatty's death really was an accident. Uncle had accidentally dropped a bag of toy balls that night, which led to the loss of control of the bus. Realizing he has made a mistake and that the agent is innocent, the Brain runs and tries to cover the windshield from reflecting light. The agent sees and recognises the Brain as he is running, but the Brain is too late, and a blinded driver runs over the agent's wife, killing her. On a later date, as the Brain is leaving the rented flat, he is confronted and stabbed by the insurance agent in the staircase, who asks the Brain why he had to harm them. The Brain looks at the sky and thinks about his own wife before he dies.

Fanis Iakovides, professor of astronomy and astrophysics, recalls his childhood memories from growing up in Istanbul. When Fanis was 7 years old, his grandfather Vassilis was an owner of a general store with a specialty in spices. He was also a culinary philosopher and his mentor. Fanis grew very attached to his grandfather who would assist with his homework using imaginative techniques. For instance, Vassilis would teach his grandson the planets of the Solar System by showing an illustration of it and replacing the planets with spices. Cinnamon took the place of Venus since according to Vassilis, "like all women, cinnamon is both bitter and sweet". Fanis also fell in love for the first time in his grandfather store's upper floor with a young Turkish girl, Saime. However, beginning with the Istanbul Pogrom in 1955, through 1978, the ethnic Greek community of Istanbul was reduced from 135,000 to 7,000 by a series of government orchestrated riots, pogroms and deportations. Most of Fanis' family is deported in 1964 with the Ankara government decision to renege on the 1930 Greco-Turkish Ankara Convention, affirming the right of Greek etablis (Greeks who were born and lived in Istanbul but held Greek citizenship) to live and work in Turkey, and most Greek citizens who lived in Constantinople were deported to Greece, despite most never having previously resided there. Since Vassilis was not a dual citizen, he was able to stay behind while his grandson Fanis and his parents were deported to Athens. Fanis had trouble initially adapting in Greece, constantly trying to spend his time in the kitchen cooking, as it was the only link between him and his homeland. However, this would upset his mother who was afraid that the boy was either severely depressed or a homosexual. Fanis grew from childhood to adulthood, preserving his culinary talents and often offering his secrets of the Politiki Cuisine to those that ask for his help. As the years passed by, and the tension between Turkey and Greece resolved, grandfather Vassilis made several promises to visit his grandson in Athens but failed to keep them. The reason for the final incompletion of this engagement was his rapidly declining health. Consequently, Fanis returns to Constantinople after three decades to visit his near-death grandfather and also runs into his old love, Saime, who is now married. Together, they reflect on their lives and the way politics managed to change everything. Fanis will eventually realize that contrary to what his grandfather had taught him, he forgot to put a little bit of "spice in his own life".

In 2005, unpopular-yet-scholarly student Morton Schmidt and popular-yet-underachieving athlete Greg Jenko miss their school prom, Schmidt being rejected by the girl he was trying to ask to be his date and Jenko being barred from attending due to failing grades. Seven years later, the duo meet again at the police academy and become friends. After graduating, the two become partners assigned to bicycle patrol at the local park. They catch a break when they arrest Domingo, the leader of a one-percenter motorcycle gang for drug possession, but are forced to release him after they fail to read him his Miranda rights. The duo is reassigned to 21 Jump Street, a revived undercover program from the 1980s, which specializes in infiltrating high schools. Captain Dickson assigns them to contain the spread of a newly-made synthetic drug called HFS ("Holy Fucking Shit") at Sagan High School. He gives them new identities and enrolls them as students, giving them class schedules fitting their previous academic performances; Jenko taking mostly arts and humanities, and Schmidt taking mostly science classes, but the duo mix up their identities. Schmidt gets a lead on HFS from classmate Molly, and he and Jenko meet the school's main dealer, popular student Eric. The two take HFS in front of him to maintain their cover, and then rush to the bathroom and attempt to vomit the HFS out of their systems, but are unsuccessful. Eric takes a liking to Schmidt, who develops a romantic interest in Molly. Jenko becomes friends with the students in his AP Chemistry class and finds himself becoming more interested in geeky hobbies and academic pursuits. Schmidt and Jenko throw a party at Schmidt's parents' house, where they are living during the course of their assignment, and invite Eric. During the party, a fight breaks out between Schmidt, Jenko, and some party crashers from another high school. Schmidt wins the fight, impressing Eric and gaining his trust. Jenko's friends hack Eric's phone to enable them to listen in on his conversations. The phone hack reveals information about an upcoming meeting between Eric and his supplier. Jenko happens to overhear conversations between Schmidt and Eric, where he catches Schmidt making disparaging comments about him. A rift between the duo grows and their official police work suffers. Schmidt and Jenko later track Eric to a cash transaction with the distributors of HFS—the motorcycle gang from the park—and a chase ensues on the freeway. They return to school, argue, and eventually begin fighting, which disrupts the school play. They are expelled from school and fired from the Jump Street program. Eric, stressed and terrified, recruits Schmidt and Jenko as security for a deal taking place at the school prom. While dressing for the prom, Schmidt and Jenko rekindle their friendship. At the prom, Schmidt is forced to reveal his identity as a cop, upsetting Molly. When they go to the penthouse, they discover that the supplier is the physical education teacher, Mr. Walters, who created the drug accidentally and started selling it to the students to supplement his teacher's salary and pay alimony to his ex-wife. Having caught Eric smoking marijuana, he was able to persuade him to be his dealer. The motorcycle gang arrives for the deal, but Molly, high on HFS, interrupts them and starts arguing with Schmidt, outing him as a police officer. As a result, gang leader Domingo recognizes Schmidt and Jenko and orders his men to kill them. Two of the gang members then reveal themselves to be undercover DEA agents Tom Hanson and Doug Penhall, former members of the Jump Street program. In an ensuing exchange of gunfire, Hanson and Penhall are both mortally wounded. Mr. Walters and Eric escape with the money and Molly as a hostage; the gang, Schmidt, and Jenko follow close behind. Jenko creates a homemade bomb and uses it to kill the gang. Mr. Walters shoots at Schmidt but Jenko takes the bullet to his arm, sparing Schmidt's life. In response, Schmidt shoots Mr. Walters, unintentionally severing his penis. They arrest Mr. Walters and Eric, successfully reading the former his Miranda rights. Schmidt and Molly share a kiss while Eric and Mr. Walters get arrested. Both officers are congratulated and reinstated in the Jump Street program as Dickson gives them a new assignment: infiltrating a college.

Astérix and Obélix must win the Olympic Games in Greece in order to help their friend Lovesix marry Greek princess Irina. Brutus uses every trick in the book to have his own team win the game and get rid of his father Julius Caesar in the process. The film is loosely adapted from the original Asterix at the Olympic Games comic book. The love story subplot between Lovesix and Irina was not featured in the original story. Brutus, portrayed here as a comical villain with no relation to his depictions in Asterix comics, is the main antagonist, although he was not even featured as a character in the original comic book.