Jack and his best friend Charlie are world-famous hackers. They and their friends, Slink, Obie and Wren, live together in a bunker they found in the subway tunnels under London, and from there, they scout out and target "bad guys" who launder money, sell drugs or guns. They hack into their accounts and take money which they redistribute through R.A.K. (Random Acts of Kindness).
The teenagers are all runaways from a London children's home, and they work hard to keep from getting caught because they don't want to go back to the home where they feel unloved and unsupported. Then the children hear about a project called Proteus that is supposed to be the most secure and amazing computer in the world. So, of course, they decide to hack it. This decision, however, sends them on the adventure of their lives.
Honestly, I had a little trouble believing that these children who had been homeless their whole lives would have access to the high-tech gear (and know-how) required to outsmart state-of-the-art security systems, but readers looking for some technology know-how added to their adventure may want to follow the Urban Outlaws (Lexile: 650; Interest Level: Grades 5-8) by Peter Jay Black on their modern-day Robin Hood adventures. This is the first book in a series. (304 p.)
One of the reasons I became an elementary school librarian is so I can read children's books.