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Investigating the STO
Though Singh's GDD bureau had been saddled with mostly trivial cases, the bombing of the Metropolitan Levitation Mass Transit System by monotheist Ben Stark and the resurgence of the Soldiers of the One terrorist group becomes Singh and his intestigators' primary focus (CAP: "The Reins of a Waterfall", "Gravedancing").
Staying mostly on the sidelines as Agents Duram and Youngblood make inquiries into the bombing, Singh steps in when he discovers a tape of the bomber, Stark, being interrogated by Youngblood one year before the bombing for possession of explosives. Singh suggests the tape be destroyed and Duram and Youngblood step up their game, inspiring a major break in the case (CAP: "The Reins of a Waterfall").
As the STO begins bombing Holocafes throughout Caprica City, Singh is initially hesitant to attribute the crimes to a resurgence of the monotheist terrorists. However, when the Inter-Colonial Court on Libran hands down a warrant allowing the search of the Athena Academy - where Ben Stark and his suspected accomplice Zoe Graystone attended school - Singh reluctantly allowed Agent Duram to proceed, though telling him to keep it "tasteful".
Following the murder of two members of the STO who were also former students at Athena Academy, Agent Duram focuses his investigation on the school's headmistress, Sister Clarice Willow. Having been alerted of accusations made to Willow by her lawyer, Director Singh once again intercedes. Meeting with Duram outside the office, Singh admonishes Duram for harassing Willow, telling him that the Athenian cleric cannot be the monotheist terror leader Duram believed she was. Singh also emphasizes that everyone at the GDD is invested in solving the murders, not just Duram (CAP: "Retribution").
With growing suspicion that the STO has infiltrated the GDD, Agent Duram misleads Director Singh with information falsely implicating Mar-Beth Willow - Clarice Willow's wife - as a confidential informant. Upon the sudden disappearance and apparent murder of Mar-Beth, Singh reveals himself to be the mole, funneling information about the investigation into the STO to Clarice Willow's cell under the alias "Alvo". As Alvo, Singh has also stolen evidence gathered from Zoe Graystone's belongings and given it Willow - a key element in her pursuit of Apotheosis. Despite this information, Duram declines to turn Singh in, lacking concrete evidence (CAP: "Blowback").
Aware of the threat Duram now poses to his position in the GDD, Singh alters video surveillance footage of a meeting with Duram to make it appear as though the agent had become a rogue. Alerting Internal Affairs, Singh takes Duram's badge and gun and removes him from the force, handing his caseload over to Agent Youngblood (CAP: "The Dirteaters").
After Daniel and Amanda Graystone attempt to intervene in Clarice Willow's plan, Singh outs himself to the STO cell as Alvo and promises to use the GDD to help Apotheosis come to fruition. Using his resources with the Caprican legal system, Singh pins the MLMT bombing on the Graystones and has them labeled as terrorists. Attempting to arrest the Graystones at their home, Singh is stopped by Cyrus Xander who holds the GDD Director at gunpoint long enough to allow Amanda and Daniel Graystone to escape and ultimately clear their name (CAP: "Apotheosis").