When a terrorist attack ruins peace negotiations between Earth and the Lucian Alliance, Lieutenant Colonel Paul Allan/Madeline Tanner leads a new SG team to investigate. But when the IOA begins an investigation of the SGC, they learn that a vast conspiracy threatens not only the future of the Stargate Program, but also the secrecy of the Stargate and the security of Earth and many other worlds. During the investigation, Allan/Tanner discovers that the military and various governments have been infiltrated. What’s more is that there is a mole within Stargate Command. This leads to the SGC being shut down pending a hearing about the future of the Stargate Program. Defying orders, Allan/Tanner continues the investigation until they discover the mole and begins unraveling the conspiracy that leads him/her to those behind the conspiracy, who call themselves the Syndicate.
The idea for the player character was similar to Ryder in Mass Effect Andromeda. You pick one as the player character, and the other becomes a supporting character.
Also, the failed negotiations and the consequences of the conspiracy would tie into the Lucian Alliance's hostility towards Earth as seen in Stargate Universe