My wife insisted I watch the John Wick films when number three was released—and I began with number three. She thought I should see the first two to grasp the concept, but I wasn’t convinced that was necessary. As it turned out, she was wrong. You don't need to have seen 1 and 2 to follow what's happening in 3. It isn't essential to watch the initial film to appreciate the second one either. You can easily drop into this series at any point and quickly get up to speed. The storyline is remarkably simple. It’s a plot you’ve encountered many times before: a highly skilled individual seeks retribution. It could be similar to Taken, or honestly, just about any movie. The story itself isn't significant. What truly stands out is the constant, visually striking action. The fighting is intense and fast-paced, and it looks incredibly impressive. The narrative isn’t anything special, but that doesn't detract from the experience because the enjoyment comes from somewhere else. Everything feels superficial, and everyone understands that... ...because we all know this is an action movie from beginning to end, and elements like plots and narratives tend to become a hindrance in films of this kind. Too much complexity can ruin it. So, you're getting fun, thrilling, visually impressive action—and it’s entertaining. It’s perfectly acceptable to acknowledge the lack of plot because that's simply what it is: a really enjoyable and engaging experience.

Source on TMDB