In a perfect world, the movie's title would be John Wick 2: Electric Boogaloo. Alas, we do not live in that world.
Netflix thought I'd like this a lot more than I did. It's OK, but eh.
At the end of the last movie, John I-just-wanna-retire-because-I-don't-want-to-be-an-assassin-anymore Wick (Keanu Reeves) has a loose end to tie up from the last movie, getting his sweet car back. This involves killing a lot of people. And mostly destroying the car. But, anyway, he's ready to bury the hatchet after that. And also burying an array of weaponry and gold coins.
But (and there's always one of those) a new bad guy shows up and coerces John into a new job: killing the bad guy's sister so that he can get her seat in some underworld crime organization.
So what ensues is a lot of violence, but we kind of get the point: Wick is the kind of guy who can take on dozens of killers concurrently, leaving them all mostly dead, while just incurring some minor boo-boos himself. I lost track of how many of these mass-carnage set pieces there were. They differ only in their settings (which, truth be told, are decently imagined).
One nice touch: Laurence Fishburne! I think he and Keanu were in some other movies too, right?
Spoiler: the movie ends with John in big trouble with nearly everyone left alive. And, oh yeah, that means John Wick 3: Parabellum. I pre-emptively declare: not going to bother.