Based on the Alex Rider novels by Anthony Horowitz, Alex Rider is a British spy thriller. London teenager, Alex Rider, who has been living with his uncle since his parents died, is recruited by a subdivision of MI6 upon the death of his uncle.
Alex's job in Series 1 is to infiltrate a 'reform' school for wayward rich kids. In the 2nd series, he doesn't have a formal role but does much of 'The Department's' work for them.
There is an additional orphan character in Series 2, Kyra Vashenko-Chao, who is a skilled gamer, hacker and programmer (reminiscent of Lisbeth Salander of the Dragon Tatoo).
At one point Kyra suggests that she and Alex form "an orphan club". He counters by saying they need a 'survivors club'.
Kyra is not a character in the books by Anthony Horowitz, but appears to be an innovation of the screenwriter for the series.