When it comes to shutter speed, there is a general rule of thumb that says you should set it at twice your frame rate, or at least as close to it as you can. So, if you're shooting at 24 fps, your shutter speed would be at 1/48 or 1/50. At 60 fps, it'd be at 1/125. 120 fps would be 1/250. You get the picture. But sometimes following this rule isn't possible, desirable, or beneficial, so is there a way to deviate this standard and still capture great images? Totally! In this video, Sareesh Sudhakaran of wolfcrow shows you not only how to break the rules of shutter speed, but why you might want to break them in the first place as well.
There are several reasons you might want to break shutter speed rules. Maybe there's a gear issue, like your lens vignetting as you stop down, like Sudhakaran's did in the video. Maybe it's a stylistic issue, like wanting to change the look of an action scene by increasing the shutter speed, like Steven Spielberg famously did in Saving Private Ryan.
Keep in mind that there are certain shooting situations that will make breaking the rule more challenging, like lighting a scene with artificial light (because of flicker) and moving elements within the frame, like rain, snow, water, or trees (because of motion blur). Now, you might actually want a little flicker or more/less motion blur in your shot, but if you don't want these effects but still need to change your shutter speed, there might be ways to make them less noticeable to your audience, like adding motion blur in post.
Sudhakaran suggests watching his video that explains in great detail what shutter speed is and how it works and I have to agree. It's an advanced lesson on just about everything pertaining to this concept, which might help give you a better understanding of the rules you're breaking, as well as why you might want to break them.