Nuclear espionage

Nuclear espionage is when someone tries to get secret information about nuclear weapons and materials, like uranium or plutonium. This can be done by spying on people who are working on nuclear projects, or stealing documents that describe how nuclear weapons work. The person who is doing the espionage is usually trying to get information to give to another country, so that the other country can make its own nuclear weapons. It's very serious, because if the wrong people end up with nuclear weapons, it can lead to lots of destruction and danger.