Battlestar Galactica

"Number Two", better known as Leoben Conoy, is a humanoid Cylon first encountered at Ragnar Anchorage. He fancies himself as a prophet with predilections for enlightened monotheistic religion, whereas he is more likely to sow the seeds of doubt or mis-information, weaving lies in the fabric of truth and faith.

Number Two is first encountered at the Ragnar Anchorage, where he poses as an arms dealer and calls himself Leoben Conoy. It is likely that he was assigned with the monitoring of this depot station as the war began, gaining intelligence on battlestars that visited there. Alternatively, he may have been tasked with stealing away or destroying the ammunition (or the station itself) to prevent its use by the Colonials.

Conoy is already sick from the radiation around Ragnar, suggesting he had been there for several hours before Galactica's arrival. He becomes trapped aboard the station with Commander Adama after a warhead is accidentally detonated. As they try to find another way out of the station, Conoy reveals his true nature to Adama through conversation, initially by claiming to be something of a philosopher. Identifying Conoy as a Cylon on the point of death, Adama challenges him and learns of the Cylon's ability to transfer their consciousness to another body when dying. Only Leoben can't -- the radiation of Ragnar is interfering with his ability as he appears to collapse.

A fight ensues, during which Conoy exhibits unnatural strength and speed. Adama manages to kill him by forcing his head over a venting steam pipe and then repeatedly bludgeoning the Cylon to death with a flashlight. He then brings Conoy's lifeless body back to Galactica for further examination. Samples from this body, when burned, reveal synthetic materials -- which permit Adama, Colonel Tigh and Dr. Baltar to deduce that the Cylons could mimic humans in appearance (Miniseries). The corpse is later stored in the ship's morgue (Flesh and Bone).