Monroe was a curious fourth-grader who loved solving mysteries. One day, as he was walking home from school, he noticed something unusual - Shawn and Kenny, his two best friends, were huddled together, whispering and looking worried.

"What's going on, guys?" Monroe asked, approaching them cautiously.

Shawn and Kenny looked up, their faces filled with concern. "Monroe, you won't believe this, but someone has stolen our pizza!" Shawn exclaimed.

Monroe's eyes widened. "Your pizza? But how could that happen?" he asked, his mind already racing with possible explanations.

Kenny explained that they had ordered a large pepperoni pizza for their after-school snack, but when they went to get it, the box was gone. "We searched everywhere, but it's just disappeared!" he said, clearly frustrated.

Monroe knew he had to get to the bottom of this mystery. "Don't worry, you two," he said, determination in his voice. "I'm going to find out what happened to your pizza."

The three friends set out to investigate the crime scene, searching for any clues that might lead them to the pizza thief. They interviewed the school staff, checked security cameras, and even searched the nearby dumpsters, but their efforts seemed to be leading them nowhere.

Just when they were about to give up, Monroe noticed a small piece of pepperoni on the ground. "Aha!" he exclaimed. "I think I know where to look next."

Following the trail of pepperoni, the friends discovered that the pizza had been taken by the school janitor, who had been secretly snacking on it in the supply closet. The janitor, who was feeling hungry and couldn't resist the temptation of the delicious-looking pizza, had tried to hide his crime but was ultimately caught thanks to Monroe's keen detective skills.

In the end, Shawn and Kenny were relieved to have their pizza back, and they were grateful to Monroe for his help in solving the mystery. From that day on, the three friends made a pact to always look out for each other and to never let a stolen pizza go unsolved.