Okay kiddo, let's talk about something called the NKVD Troika. It might sound like a silly word, but it's actually a very serious thing that happened in history.
First, let's break down what NKVD Troika means. The NKVD was a secret police force in Soviet Russia (that's a country far away from where we live). Troika means 'a group of three', so NKVD Troika was a group made up of three people from the secret police force.
Now, what did this group do? Well, during a time when Soviet Russia was going through some big changes, the government started to get very strict about who they thought was being 'unloyal' or 'disobedient'. They decided to use the NKVD Troika to find and punish these people.
The way they did this was by holding trials that weren't really fair. The three people from the NKVD Troika would make quick decisions about who was guilty and what punishment they should give out. They didn't really care if people were actually guilty or not, they just wanted to show that they were in charge and that they could punish anyone who went against them.
As you can probably guess, this was a really scary time for people in Soviet Russia. Anyone who spoke out against the government or even expressed their own opinions about what was happening could be accused of something and then punished by the NKVD Troika.
So, to sum it up, the NKVD Troika was a group of three people from a secret police force who held unfair trials to punish anyone they thought was being disobedient or unloyal to the government. It was a really scary time for the people of Soviet Russia.