Murdering at the school

The plan

Kyle was in his room, talking with Jimmy on the phone:
"What's happening in the school?"- asked Kyle
"There are many kids who are saying that Henry was murdered."- said Jimmy
"What does the headmaster does to them?"- asked Kyle
"They go to his office , and after that, they never ever mention Henry's name again"-said Jimmy- "I spend all the breaks with my sister. She always wants to go to that dark place but I can't let her. There's still a killer out here. I just feel pity for those who don't know it"
"I have got to get prepared for Henry's funeral. Are you going?"- said Kyle
"I'd like to go, but I can't. I'm busy."- said Jimmy
"Bye"- said Kyle
"Bye"- said Jimmy
Kyle turned off the phone. His dad entered the room.
"I had lots of work to convince Charles to collaborate with Pincher and to convince your mother that you were sick"- said Frank
"Dad, I need to tell you something..."- said Kyle
"What, son?"- said Frank
"I'm sorry dad. You were right. There's lots of crime, even in Lisbon. I should have listened to you early. It could be me in that day, you know? I was alone too, walking on the rain."- said Kyle
"Don't worry son, I understand. When I was your age I was exactly like you. Now go take a shower because uncle Charles is almost here"- said Frank
"Just one more thing dad"- said Kyle
"What, son?"- said Frank
"I think you should fight them."- said Kyle
"Fight who?"-said Frank
"Your boss and the headmaster"- said Kyle
"Kyle, you know that I need this job..."- said Frank
"There's a killer out there dad! They didn't even let you examine the dead body!!! It could be them! Think about what I just said to you dad"- said Kyle, getting out of the room and going to the bathroom.
It passed 10 minutes, and finally the doorbell ringed. It was Charles and his wife. They were dressed all in black.Kyle's mom opened the door. She didn't chose her clothes, so she called Charles' wife to help her choose it. Charles and Frank were alone in the living room:
"Charles, I've been thinking."- said Frank
"What Frank"- said Charles
"We need to fight Percy and Pincher"- said Frank
Charles smiled
"I knew you were going to say that"- said Charles- "So, what's the plan?"
"We just got to make Percy talk about that little shitty plan and record it. We call other cops to the delegacy and give them the recording. Then, Percy is arrested, we siege the school, evacuate it, arrest the headmaster and investigate the school."- said Frank
"I like that plan"- said Charles