They’re all clones?

“What do you mean?” Shepard asked.

“Everyone besides you and me is a fake,” EDI said.

“How do I know that you are real?” Shepard asked. “Tell me something only the real EDI would know.”

“Jeff has over 200 million terabytes of pornographic material,” EDI replied.

Shepard raised an eyebrow. “Okay… fair enough… but I don’t understand. How could they possibly be different people? When would they have switched?”

“Most likely when you were dead,” EDI said. “The second time I mean. It would have been the only time there would be an opportunity for a switch to occur.”

“So what? They’re all clones?” Shepard said. “Even Tali?”

“It appears Cerberus had contingency plans when you destroyed their base,” EDI said. “The person behind this also had information on you and every member of the team.”

Shepard’s eyes widened. “So they were able to mimic everyone’s likely choices and behavior… but where are the originals? And who even did this?”

“Most likely one of your enemies,” EDI said.

“Thank you, EDI,” Shepard said with sarcasm.

“You’re welcome,” EDI said.

“EDI, I need you to run matches on every person on the Normandy. I need to be certain that everyone is who they’re supposed to be. Also run analysis on Aria T’Loak and Tela Vasir.”