With Friends Like These...

"Make your choice. Make your kill. I just want to observe... and admire."

- Astrid

It is immediately preceded by Innocence Lost, and is a continuation of those events.

Background
See: Innocence Lost

Objectives

 * Kill one of the captives
 * Speak with Astrid
 * Enter the Dark Brotherhood Sanctuary
 * Speak with Astrid

Walkthrough
After the Innocence Lost quest has been completed, a courier will appear and give the Dragonborn a note with the imprint of a black hand and the words "We Know" written beneath it. The courier generally takes between one and three days to arrive, depending on how much you move around the lands of Skyrim.

Once the note is received, sleep in any bed.


 * Note: For some reason, the bed cannot be in Windhelm (where you got the quest "Innocence Lost..." from Arentino). The Quest does continue as normal in any other bed in the game.

Note: If you sleep in a bed after completing Innocence Lost, you will not begin this quest. Wait for a full day and you will receive the courier's message (it will happen without a note.)

The Dragonborn will awake in an Abandoned Shack, located in the marshes north of Morthal. A Dark Brotherhood assassin named Astrid will speak to the Dragonborn. She reveals that the Dark Brotherhood is aware of their murderous deed and is pleased that Grelod is dead, but since the Aretino child performed the Black Sacrament, they demand that a debt be paid for the kill that was stolen from them. Astrid has brought three other people to the shack where the Dragonborn awoke. Fultheim the Fearless, Alea Quintus, and Vasha are tied up and wearing an execution hood, but able to answer questions. Astrid tells the Dragonborn that there is a contract out on one of their lives, and the Dragonborn must figure out who to kill.

To join the Dark Brotherhood, kill any combination of the three. The Dragonborn will be rewarded with an initiation to the Brotherhood regardless of their choice. Alternatively, killing Astrid will close the option to join the Dark Brotherhood and a new quest, Destroy the Dark Brotherhood! will begin. The Abandoned Shack cannot be left without killing one of the three prisoners or Astrid.

Kill Choices
Each kill, including killing all three of the possible victims, invokes a different response from Astrid upon speaking to her afterwards.

Killing the Khajiit:
"'The conniving Khajiit. Cat like that was sure to have enemies. It's no wonder you chose him.'"

Killing the mother:
"'Ah, the feisty goodwife. Quite the mouth on her. Someone must have wanted her dead... right?'"

Killing the Nord warrior:
"'Oh ho. The whimpering Nord, eh? Yes, yes, I can see how you'd come to that conclusion. Interesting choice.'"

Killing all three:
"'Well, well. Aren't we the overachiever. Three possibilities, three victims. Must have been one of them, right? So why take chances...'"

Killing the Khajiit and the mother:
"'Hmm. The fearless wife and mother, and the underhanded Khajiit. Had to be one of them, right? Interesting choice.'"

Killing the Khajiit and the Nord warrior:

 * "The timid warrior and the sly Khajiit. Must have been one of them, right?"

Killing the Nord warrior and the mother:

 * "The blubbering barbarian and the tenacious mother. Must have been one of them, right?"

Killing Astrid
"'...Well...done.'"