Beelo Gurji was a salarian operative of the Special Tasks Group. In 1493 CE, he was accused of using thirty civilians as bait during the course of one of his missions -- using them to find his target. Instead of incarceration, the Citadel Council offered him the opportunity to establish the Spectres. Beelo agreed, becoming the first of the elite branch.
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Beelo Gurji is derived from Mass Effect. For canon information, please visit Mass Effect Wiki.