James finds it easy to befriend Junior, the son of the main drug dealer. They skip school and do all kinds of hooligans. Junior asks James to come by the boxing gym. James is a shoe in, as CHERUB members are taught martial arts and are fit from training.
Kerry wants to prove herself and gets info from a boy whose father is aligned with this drug trade. Kerry has James and his little sister Lauren come and help break into a warehouse where she thinks there are drugs. It is a grand success. But the cops just monitor the place now for info.
James accepts an invite from Junior and his dad to fly to Miami. Apparently some cartel broke ties with Junior's father, and they come in strong to try to beat info on his hidden money. James and Junior come upon the scene. James runs. A gunman follows. James uses a broken piece of plaster to stab the perpetrator, steal his gun, and fire one bullet to kill him. James later drives a Range Rover out of the compound.
The DEA in the USA arrest Junior's father. He gets sent back to Britain after cutting a plea bargain. The British court system was not as lenient. He got 18 years in prison. No parole until at least 10 years served. James is benched because he was on two big missions this year. Plus his school work has fallen behind.