This story would follow a young rebel, living under the oppressive rule of the monarch in Keldaron. Them and their teenaged friends attack a royal carriage they believe to be transporting gold or jewels or something valuable, but instead they find it is transporting the prince or princess. Some in the group believe they should kill them. Others believe they should ransom them back to the capitol. The main character is conflicted. The group decided to take them captive while they make a decision.
Maybe the main character forms a connection with them and decide to let them go. As soon as they get back to the capitol, the royal soldiers come and find them. Maybe they kill most of the group, but the main character wasn't at their camp, or in the village or wherever they were staying. (maybe they raze the entire village) MC gets back to see this and makes it their mission to get revenge.
They eventually get to the capitol and break in. They find the price or princess or whoever, wanting them dead. But they find out somehow that they actually didn't want them dead, they didn't send out the soldier, someone from the original crew at the carriage somehow found out where they went and sent them in. (maybe simply followed them from the carriage or something) The prince or princess tried to stop their parent from sending in the soldiers, because MC had been kind to them and released them, but it was too late. (not that it would have mattered anyway, the parent is basically and evil dictator)
Not sure what will happen next.
This feels like it could make a good novel, or maybe just a novella.