Leoben Conoy is a Cylon agent first encountered at Ragnar Anchorage. He fancies himself as a prophet with predilections for enlightened monotheistic religious dogma, whereas he is more likely to sow the seeds of doubt or mis-information, weaving lies in the fabric of truth and faith.
Ragnar Anchorage Copy
Conoy is first encountered at the Ragnar Anchorage, where he poses as an arms dealer. 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.
Conoy 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, Leoben 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.
A fight ensues, during which Leoben exhibits unnatural strength and speed. Adama manages to kill Conoy by forcing his head over an outventing steam pipe then bludgeoning him to death with a flashlight. He then brings Leoben's body back to Galactica for examination. Samples from this body, when burned, revealed synthetic materials -- which permitted Adama, Colonel Tigh and Dr. Gaius Baltar to deduce that Cylons could mimic humans in appearance (Miniseries).
The body is later stored in the ship's morgue (Flesh and Bone).
Later, three copies of Leoben are among the group of Cylons that rescue Aaron Doral, abandoned on Ragnar by the Colonials after Dr. Baltar fingers him as a Cylon agent, and debrief him.
Gemenon Traveller Copy
Conoy is again encountered when a copy is found apparently stowing away aboard the Gemenon Traveller. Knowing the model's ability to weave fact, fiction and outright lies into a confusing fabric of truth, half-truths and deceit, Adama wants the copy destroyed. However, he is overruled by President Roslin, who demands the model be interrogated.
Lieutenant Kara "Starbuck" Thrace is assigned to interrogate Conoy aboard the Gemenon Traveller. Over the course of eight hours, Conoy demonstrates his ability to confuse and mix truth with lies: he claims to have planted a nuclear device somewhere in the fleet, but will not reveal where. He also mixes what appears to be religious mumbo-jumbo with penetrating insights into Colonial philosophy and Starbuck's own past (Flesh and Bone).
While she resorts to ever-more drastic measures to obtain details on the alleged bomb's location, Starbuck finds herself being drawn into Leoben's vision of life. So much so that when Roslin orders his execution, Starbuck very much empathises with him.
Prior to his death, Conoy reveals there is no bomb, and uses a reason suggested by Starbuck in the initial stages of his interrogation: that since he is so far from other Cylon centers of influence, he cannot transmit his "soul" back to home should his body die. However, the real purpose of his mission is revealed when President Roslin arrives aboard the Traveller and he manages to whisper to her that Adama is in fact a Cylon -- thus planting a potentially dangerous seed of doubt between her and Adama.
Convinced now of the danger in keeping Conoy alive, Roslin orders him ejected from the Traveller's airlock.
Interestingly, Roslin had a premonition of Conoy's surfacing in the fleet when she had a dream about him at the time he was captured. Later, in her cabin on Colonial One, she had a vision of him talking to her which prompted her decision to visit him in person - thus allowing him to complete his mission.
At the time of the dream and the vision, Roslin assumed both were the result of her using Chamalla to treat her cancer. However, both may have been the result of some form of psychic ability on the part of Conoy.
Other Copies
Apparently the Caprica Resistance captured and interrogated their own copy of Conoy, as Samuel Anders sarcastically quotes his philosophy to Kara Thrace (Resistance). This is speculation, of course.
A Leoben or two are witnessed in the background of the park and cafe scenes in "Downloaded"; however, these are played by a stand-in as Calum Keith Rennie was unavailable for the episode.
During the Cylon invasion of New Caprica a Leoben copy slips into Kara Thrace and Samuel Anders' tent and asks the ailing Anders where Thrace is (Lay Down Your Burdens, Part II). It is uncertain if this is the Ragnor Ancorage Leoben, Kara's Leoben that she interogates, or another copy altogether.
Notes
- Conoy is the name of a township in Lancaster County, Pennsylvania.