Skeleton Key (English, Paperback, Anthony Horowitz)

Teenage superspy Alex Rider is enlisted by the national security services again – this time for a routine reconnaissance mission at the Wimbledon Tennis Championships.
But before long, Alex finds himself caught up in a terrifying chain of events that leads from the Chinese Triad gangs in London to an undercover assignment in Cuba. Alex begins to make chilling links between suspicious deaths, an illegal nuclear weapons deal and the plans of his host, Russian General Sarov, for the future of the world…
Source- Goodreads.com
A2