IT - O Interrogator The IT - O was an interrogation droid designed by Imperial Security Bureau and employed by the Galactic Empire . Use of the IT - O was carefully controlled by ISB , though some models found their way into the hands of senior Moffs , military intelligence and even CompForce . They were also employed by Imperial Inquisitors and Stormtrooper garrison commanders . Characteristics . It was a hovering droid similar in appearance to a remote , perhaps a third of a meter in diameter , with various attachments , deliberately frightening in appearance , used in torture . The droid was generally successful in getting information from prisoners using elaborate and scientific torture methods . First , it would inject the prisoner with a mentally disabling chemical that would decrease the pain threshold , while also forcing the subject to remain conscious . IT - O would do a read on the body , detecting the most sensitive areas like the genitals , joints , neck and many other less obvious body parts . Occasionally , the prisoner ' s vision may be obscured . A single torture session would usually last well over an hour . The droid had onboard systems to record the entire process , in case any information was lost in the screams of the prisoner . Its reputation was so feared that many prisoners began reciting their sins as soon as they saw an IT - O floating into their cell . The IT - O ' s injection reservoirs could be filled with the latest drugs engineered by Imperial experts , such as Bavo Six and OV600 . The droid could perform interrogation by itself or in conjunction with living questioners . It was designed with an emotionless personality to ask questions in flat monotone . When working with a living assistant the IT - O would often say nothing at all , thus making the prisoner fear and hate the droid , while viewing the living interrogator as a source of potential mercy . Many Imperial Officers realized that the droid ' s fearsome reputation was so great that they would make good guard droids and so posted them at access points to sensitive areas of their bases and starships . This worked for all but the most determined opponent , as the droid would often cause the infiltrator to panic and run , usually straight into the arms of a stormtrooper . History . One such droid was used by Darth Vader in his interrogation of Princess Leia Organa in 0 BBY . When Leia Organa underwent her mind probe , she was injected with a powerful mind - altering hallucinogen that made her very susceptible to suggestion . With mere words from Darth Vader , Leia imagined herself in unbearable pain , though she was not undergoing any physical harm whatsoever . Her uncanny fortitude prevented her from divulging any Alliance secrets during this torment . IT - O models also did guard duty within Detention Block AA - 23 , with Luke Skywalker encountering such a model while trying to rescue Leia . IT - O models , along with Remote s and Arakyd Viper probe droids , were used heavily as guard droids in Moff Rebus ' s underground sewer lair , as well as the Imperial Detention Facility on Orinackra , the ISO Building on Imperial Center , the Executor , and the Arc Hammer . Eventually , the IT - O model would be succeeded by the IT - 3 Interrogator . Behind the scenes . The IT - O prop used during the filming of " A New Hope " had the words " British Made " as well as " 200° C " on its hypodermic needle . Although the lettering on the droid ' s hypodermic is illegible to most viewers when examining the scene on VHS , DVD , and high - definition television broadcasts , some viewers claim to be able to read the writing . " A New Hope " listing on the used to claim that the label reads " Made in England " . The actual prop used for the interrogation droid has been exhibited in museums . Photographs of the prop as displayed show that lettering does appear on the syringe , but that it actually reads " British Made . " The IMDb entry has since been updated . In the " Marvel Star Wars " adaptation of " A New Hope " , the mind probe of Princess Leia is performed by what appears to be a RA - 7 protocol droid rather than an IT - O . A reference to the IT - O was made in the video game " " , in which the droid G0 - T0 is similar in appearance , but seems to be inverted .