Throughout Mass Effect 3, you're likely to make several trips to the Citadel at various times. After all, this is where most of the characters not on your ship are stationed. However, you don't just visit the place to chat with friends. There are also a bunch of quests on the station that require your attention.

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One of them is called Hanar Diplomat, which revolves around the Reapers and the Hanar homeworld. You hear about it from a Spectre called Jondum Bau, who sends you an email asking to meet. This is how you find him and complete the rest of the quest.

You must do this quest before Priority: Tuchanka. Afterward, it will no longer be available.

Find And Speak With Jondum Bau

To get the assignment, you must meet with Jondum Bau, who becomes available after Priority: Palaven. So go to the Embassies on the Citadel and head in the direction of Commander Bailey's Office (C-Sec Office on the map). The Salarian is standing right outside the room.

When you engage him in conversation, he briefs you on the situation, explaining that a Hanar diplomat could be indoctrinated. To start the investigation, you head into the Spectre Office, where Kasumi might be waiting if she's still alive. She will join you on your mission.

Track The Hanar

To find out if any Hanar diplomats are under Reaper control, you must track their activity. To start, interact with the Spectre Terminal and enable the Hanar Embassy Tracking. After that, you must search for the terminals.

Terminal One Location

The first is right on the other side of the Embassies area. It's on the wall, near some windows and benches. When you find it, bypass the thing.

From the terminal, you learn about some odd transactions by two different Hanar diplomats. One is clean - at least politically so - while the other requires more investigation.

Terminal Two Location

For terminal two, you must go down to the Docks: Holding Area. This one is easy to find, as once you get down to the docks and exit the elevator, it's immediately on your left.

Bypass this one to find out that the Hanar you learned about from the last terminal clearly isn't indoctrinated, as he's supporting the war effort. This puts you on the trail of the Hanar opposing him, who's recently arrived on the Citadel.

Terminal Three Location

To reach the third terminal, you must head all the way through the Docks: Holding Area to point of interest number four on the map - past all the cargo crates. From there, you can find it on the wall to the right.

Like with the last ones, bypass it. This will have you send Bau a list of new Hanar arrivals, but the list includes face names instead of soul ones, which is not what you need.

Terminal Four Location

Terminal four is also terminal two, as you need to return to the one next to the elevator.

When you bypass this one, you find out the identity of the indoctrinated Hanar. So, your next objective is to stop him.

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Confronting The Hanar

Now that you know which Hanar is under Reaper control, you must head to their office. Thus, return to the Embassies and head to terminal one to find Bau. Interact with him to trigger a scene where you confront the Hanar.

You can either ask for the Hanar's reasons or skip straight to arresting the creature. Whatever you do, the Hanar reveals that they've just sent a virus to disable the defenses of their homeworld, which would allow the Reapers to invade.

However, Bau says he still has time to block the upload. But a human by the door starts attacking the Spectre. What occurs from here depends on whether Kasumi is around or not.

If Kasumi is there

If Kasumi is around, things are a lot easier. She immediately jumps to the terminal to stop the upload while you help Bau. The Salarian then kills the Hanar, as Kasumi halts the virus. However, there is a fail-safe that explodes, throwing the thief against the wall.

She pretends to die, so Bau will stop trying to arrest her, and Shepard won't ask her to be a part of the war effort. It works on the former who leaves. But if you gained Kasumi's loyalty in Mass Effect 2, your Shepard won't be fooled. Instead, you will confront her and ask her to help the scientists on the Crucible.

This method also grants you war assets from Bau and Hanar/Drell forces as the quest comes to a close.

If Kasumi Isn't Around

Without Kasumi, you must make a choice. You can either save Bau by hitting the Renegade Interrupt or stop the upload. Naturally, if you don't rescue the Salarian, he dies. But if you don't stop the upload, the Hanar homeworld is attacked.

Saving Bau earns you Spectre war assets. Alternatively, stopping the virus grants you Hanar and Drell forces. Either way, the quest ends.

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