All of these agents began working for German government but soon all of these agent double crossed Germany to become British agents. Why would someone became a double agent? Some would do it for personal gain, or because they don't enjoy watching the country who they sworn to protect hurting innocent lives, or the agent tries to seek approve from multiple sources because as a child they weren't given acceptance from their parents, or maybe they are bored. A double agent is a person who engages in activity for two intelligence or security services. The double agent often has access through his travels for the other service to positive intelligence on that country, or on third countries of interest to the controlling service. A double agent can be an asset to a country or there worse nightmare.