You ever notice how there are so many cop shows following homicide detectives on TV? Or murder mysteries lining bookstore shelves? You might love stories about murder, or you might find them repetitive and boring. But hidden in their popularity are some very useful lessons about writing.

To demonstrate, here’s an experiment you can perform on your friends or coworkers. Before I get into the details, let me give you a little warning:

DO NOT DO THIS EXPERIMENT.

It is a terrible idea! It will lead to horrific things!

Okay, here’s how to do the experiment. First, find someone in your life who finds murder stories of any kind boring or oversaturated. Cop shows, murder mysteries, slasher films, it doesn’t matter. Bonus if the person used to like them but has gotten burnt out or desensitized.

Then threaten to kill them. Really threaten. Don’t just say “I’m going to kill you!” with a little laugh over your morning bagels. You’ve got to sell it. Show up in their house at night in a mask and a butcher’s knife. Hell, make it a hockey mask. The fun part of this experiment is that you can throw in all the cliches you want and it’ll still work.

If you don’t want to get arrested, you could instead anonymously send them a picture of their kids with red Xs drawn over their eyes in blood. Bonus it matches their children’s blood types. You may be able to find this information through company records. Just save Doris over in HR the last Boston Creme donuts. Or whatever she likes. Be creative!

Keep this up for a few days. Long enough that the co worker will have trouble passing it off as a joke. Long enough to really get under their skin. Then, when they are at their most stressed, tense, and frightened, go up to them and ask, “So, are you bored?”

Three guesses what their answer will be.

So, what can we learn from this little experiment that YOU WILL UNDER NO CIRCUMSTANCES UNDERTAKE, AND IF YOU DO IT ISN’T MY FAULT?

You can be confident that your little stunt not only caught your victim…uh, subject’s attention, it also shoved everything else out of their mind. The imminent threat of murder moved to the very top of their priority pile. Even if they had a big promotion coming up. Even if they were under a lot of stress from an impending divorce, or about to land a big deal that could let them afford that vacation home in Majorca they always wanted.

People aren’t bored of things that feel real to them. But some things feel a lot more real than others. This is an extreme example, but it hides some truths that have meaning when it comes to fiction. You can write a great story about someone getting a promotion or landing a big deal. But you have to work a lot harder to make it feel real.

Make someone feel threatened by your antagonist and you’ve got them. Make them feel like this person is so dangerous it trips their brain’s ability to tell the difference between reality and fiction, like when you are sure there is something in the darkness waiting for you. Or you are terrified when your children are 20 minutes late getting home because it’s dark, and anything could be out there.

Murder is easy. Sure, it’s fun watching competent detectives and brilliant super-sleuths outwit savvy criminals. But that’s not the real reason 20 new cop shows hit the network line-up every fall. Murder, done right, sucks people right in because it is visceral. It is primal. It is easy to make it feel so real it is undeniable.

You don’t have to write about murder. But the lessons of murder reach past the edge of the knife. Make your tension threatening and your antagonists terrifying—even if the threat they represent is non-murderous in nature—and you’re already halfway to Majorca.