The Fall - Robert Muchamore

In this action-packed CHERUB novel, two siblings on separate special agent missions both end up in deadly danger.
CHERUB agents are highly trained, extremely talented--and all under the age of seventeen. For official purposes, these agents do not exist. They are sent out on missions to spy on terrorists, hack into crucial documents, and gather intel on global threats--all without gadgets or weapons. It is an extremely dangerous job, but these agents have one crucial advantage: Adults never suspect that teens are spying on them.
In The Fall, when an MI5 operation goes disastrously wrong, James needs all of his skills to get out of Russia alive. Meanwhile, Lauren is on her first solo mission, trying to uncover a brutal human trafficking operation. And when James does get home, he finds that his nightmare is just beginning...