No plot details have been revealed yet for John Wick: Chapter 4 yet, although John Wick: Chapter 3 – Parabellum certainly laid the groundwork for things to kick up a notch in this world.
Angry at The High Table for how it’d retaliated against him, Bowery King asked John if he was also angry, and the protagonist answered affirmatively.
After being shot by Winston and falling off the rooftop of The Continental, the badly injured John was retrieved by The Tick Tock Man and brought to The Bowery King, who was recovering from being slashed up as punishment for helping John in Chapter 2.
So now the stage is set for these men to exact revenge on the ruling council of crime lords in Chapter 4.