Less than an hour after the events of the second film, former hitman John Wick is now a marked man and on the run in Manhattan, with his dog. After the unsanctioned killing of crime lord and new member of the High Table Santino D’Antonio in the New York City Continental, John is declared “excommunicado” by the Table and a $14 million bounty is placed on his head that rises each hour. On the run from numerous assassins, John visits the New York Public Library and retrieves a crucifix necklace and a “marker” medallion from a secret cache in a book. He visits the Director, the head of the Ruska Roma, a crime organisation he once belonged to, and who refers to him by his birth name: Jardani Jovonovich. She accepts the crucifix as a “ticket” for safe passage to Casablanca, Morocco.
Meanwhile, an Adjudicator of the High Table meets with Winston, the manager of the New York City Continental, and the Bowery King, the leader of a network of vagrants. The Adjudicator admonishes both for helping John in the Santino killing and aftermath, and both are given seven days to give up their offices. Soon afterward, the Adjudicator hires Zero, a Japanese assassin. They find the Director, whose hands are pierced by Zero as punishment for helping John.
In Casablanca, John meets Sofia, a former friend and the manager of the Moroccan Continental. He presents his marker and asks Sofia to honor it by directing him to the Elder, the only person known to be above the High Table, so that he can request to have his bounty rescinded. Sofia takes him to meet Berrada, her former boss, who now runs the mint that manufactures the gold coins of the assassins. Berrada tells John that he may find the Elder by wandering through the desert until he cannot walk any longer. In exchange, Berrada asks for one of Sofia’s dogs; when Sofia refuses, he shoots the dog (who is wearing a bulletproof vest at the time, so is unharmed). In retaliation, Sofia shoots and wounds Berrada, and the duo fight their way out of the kasbah and flee into the desert. Having fulfilled her marker, Sofia leaves John in the desert. Meanwhile, the Adjudicator, accompanied by Zero, confronts the Bowery King because he did not agree to leave his position after seven days. As penance for assisting Wick previously with seven bullets, Zero maims the Bowery King with seven cuts.
In the desert, John collapses from exhaustion but is found and brought to the Elder. John says that he is desperate to live on to “earn” the memory of the love he once had with his wife. The Elder agrees to forgive John on condition that he assassinate Winston and continue to work for the High Table until his death. To show his commitment, John severs his ring finger and offers his wedding ring to the Elder. John arrives back in New York City and is pursued by Zero’s men. Zero nearly kills John before his pursuit is halted as they arrive at the New York City Continental. Charon, the hotel’s concierge, reminds Zero that no “business” shall be conducted on hotel property, lest he be declared excommunicado himself. John is allowed to meet with Winston, who encourages John not to die as an enslaved killer but as a man who loved, and was loved by, his wife.
The Adjudicator arrives, but Winston refuses to give up his office, and John refuses to kill Winston. As a consequence, the Adjudicator “deconsecrates” the New York City Continental, revoking its protected neutral ground status. The Adjudicator notifies Zero and sends heavily-armed and armored High Table enforcers as backup. Winston furnishes John with weapons from the hotel, and alongside Charon and other hotel staff, John defends the Continental from the enforcers. John is subsequently ambushed by Zero and his students. John kills all but two students, and then fatally wounds Zero.
The Adjudicator negotiates a parley with Winston, who explains the rebellion as a “show of strength” and offers penance to the High Table. John arrives, and when the Adjudicator identifies him as a threat to the negotiation, Winston shoots John repeatedly in the torso, causing John to fall off of the Continental’s roof. The New York City Continental returns to operation and is “reconsecrated”, but the Adjudicator informs Winston that John’s body has disappeared, and that he remains a threat for both of them. Meanwhile, a seriously injured John and his dog are delivered to a now heavily-scarred Bowery King. He tells John that he has had enough of the High Table and will be rising against them; John agrees to join him in his efforts.
