Imperial Investigation Service

The Fifth Service, formally known as the Fifth Directorate, was the main child agency within the Imperial State Security Committee, in charge of carrying out investigations of various types on behalf of the Committee. Every major world of the Empire had a State Security Office on it, and each one was staffed by a number of agents from each of the five directorates, including Investigation.

History
Formed in 19 BBY by order of Emperor Palpatine himself, the State Security worked upon the personal orders of the Galactic Emperor, Darth Vader, and the Imperial Ruling Council. They were formed as a result of the rivalry between the Imperial Intelligence and the Security Bureau. The two agencies were too busy assassinating each other to work against the Rebel Alliance, so Palpatine ordered the creation of the State Security as a result. Operations was one of the five directorates formed, each carrying out a certain task.