Shortly after Baltar comes on board Galactica, Head Six reveals that a device which he had previously seen in possession of Six on Caprica has been surreptitiously installed in Galactica's Combat Information Center (CIC) (the command and control center of the battlestar). Head Six tells him it wasn't her job to put it in there. Baltar realizes there is a Cylon on board Galactica, but knows he cannot reveal that information, or indicate the device is not a part of the ship without implicating himself in the destruction of the Colonies. Baltar decides to implicate a person on board who goes by Aaron Doral because he is a civilian who has had access to the CIC during the last several weeks and, as an outsider, would be more likely to not be trusted by the Galactica crew. Having already been put in charge of testing the fleet for Cylons, Baltar informs the Executive Officer that he discreetly collected hair samples of crew members and has found Doral is a Cylon. Baltar, however, had no method at the time for testing for Cylons in the fleet. Baltar also explains he saw Doral doing something with a strange-looking device in the CIC he does not recognize. This forces him to develop an actual method for testing the fleet for Cylons, having already "demonstrated" an ability to do so. The process he eventually creates is reliable and is done through the testing of blood samples, but is time-consuming (it takes 11 hours to test one person).