Warning: Spoilers for John Wick: Chapter 4 Below! John Wick: Chapter 4 introduces an old friend of his named Caine, and there are clues in the film that shed some light on Caine's backstory and history with John. After the events of John Wick: Chapter 3 - Parabellum, John Wick (Keanu Reeves) heads into his final showdown with the High Table. Though he has allies like the Bowery King (Laurence Fishburne) and Winston (Ian McShane) on his side, the High Table official known as the Marquis de Gramont (Bill Skarsgård) assembles an assassin army to take out John.

John also finds himself up against his old friend, the blind assassin Caine (Donnie Yen), who is forced out of retirement to assassinate John under threat of his daughter being executed. Caine is a formidable opponent for John Wick, and also becomes his strongest ally in the movie when the two team-up in the final act. Both of these sides of their relationship could reveal more details about Caine's largely cryptic past, with Caine's role in John Wick: Chapter 4 hinting that John and Caine have worked side-by-side as assassins before.

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John & Caine Probably Worked Together Before RetiringJohn Wick and Caine in John Wick 4

John Wick: Chapter 4 establishes John and Caine's past friendship early on when Caine receives his assignment to hunt down the legendary Baba Yaga, and on its own, this is curiously revealing about their past. Caine says that John has few friends and a limited circle of people that he trusts, which certainly makes sense for a man in John's position, but John's circle has also probably been limited for a long time due to the nature of his profession. Put simply, the literal cloak-and-dagger rules of the High Table puts the assassins living under it in a position of limiting their social circles.

John Wick might interact with people in the wider world on a day-to-day basis, but it is highly unlikely he would be discussing his life as the Baba Yaga with people he could not divulge that information to. With Caine also being an assassin under the High Table, that barrier would be completely removed between the two of them. This also points to team-ups on assassin missions being how John and Caine's friendship began. That is further illuminated by Caine's own role in John Wick: Chapter 4.

John & Caine's Fight Scenes Hint They Were Partners On Previous JobsJohn Wick 4 Post Credits Scene

When Caine is first tasked with assassinating John, he clearly is reluctant to do so. Their initial meeting is a tense one, with both John and Caine waiting for the other to be the first to pull the trigger. In John and Caine's confrontation in the Osaka Continental, the two are also very evenly matched. Additionally, John and Caine's dialogue exchange here, discussing the specifics of their retirements, suggests each had at least some awareness of the "deal" the other took to get out of the job. John Wick and Caine being former assassin partners could explain both aspects of their fight scene.

In the ending of John Wick: Chapter 4, John and Caine join forces in real time to fight past the hired assassins of the Marquis de Gramont in order to make it to their duel on time, and John and Caine make an unstoppable team together. The level of coordination seen between John and Caine might be another clue to their past. On the surface, John and Caine's team-up might play like an alliance formed on the fly, but their skill in combat together suggests they have done this before, further hinting to their possible past together as partners on assassin missions.

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Why John Wick Never Mentioned Caine Before

Donnie Yen as Caine in John Wick Chapter 4 pic

Caine's debut in John Wick: Chapter 4 is exactly that, with Caine having never been mentioned at all in the previous three movies. His and John's possible history as assassin partners could help explain that. John and Caine each went to great lengths to be able to retire, and their meeting in John Wick: Chapter 4 is very likely the first time they have seen each other in years. That could suggest John and Caine went their separate ways not due to a falling out, but simply out of their individual focuses on building new lives away from their time as assassins.

With John having been retired for five years and married to his late wife Helen, his focus was on his freedom, but stepping away from assassin life also probably brought stipulations with it. John keeping the old partnership he may have had with Caine hidden from anyone outside of High Table purview was probably one of them. Moreover, even once he re-entered assassin life, John did not intend for that return to be permanent. All of that together gave John Wick little reason to mention Caine until fate brought them face-to-face once more in John Wick: Chapter 4.