Skyrim's Dark Brotherhood launch doesn't make any sense
Even the Dragonborn wasn't immune to the Dark Brotherhood's murky ways in Skyrim, and it looks like Astrid has some mysterious intentions.

Of all the factions in Skyrim, the Dark Brotherhood is by far the most mysterious - and while a great deal of its secrets have been unraveled as the Dragonborn grew closer to the order, there is still one mystery that has yet to be solved. Surprisingly, this has nothing to do with becoming the Listener, the Night Mother's awakening, or even Astrid's eventual betrayal of the guild. Instead, it's about the player's first encounter with the leader of the Dark Brotherhood himself.
Being kidnapped and waking up in a room next to three hostages is a jarring but still fitting start to the questline. After explaining that the Dragonborn stole the faction's kills on Grelod, she demanded that they have to end another life to pay off the debt (much like previous Elder Scrolls titles had Dark Brotherhood players kill before being recruited). She claims that someone in the room has a death pact on their head, and it's up to the player to decide which one. As it turns out, she wasn't lying - but the truth is more complicated than it appears.
It's Unclear Which Hostage Is Guilty In Skyrim's Dark Brotherhood Quest

Unfortunately, can't tell which one The three victims are the correct targets in Skyrim. When questioned by the player, each character provides a vague backstory that doesn't reveal much about their identity. Ironically, Fultheim The Fearless is an anxious Nord warrior who admits that he may have gotten carried away in his past military duties. Alea Quintus, though haughty, looks like a weary single mother who would do anything for a child that players can adopt in Skyrim. Khajiit Vasha is probably the most logical choice of the three, as he brags about his criminal history and even blatantly threatens the player.
However, no matter which hostage (or hostages) the Dragonborn choose as their sacrifice, the outcome of the quest is the same. Astrid will neither confirm nor deny which character was the correct choice, and players are free to leave the abandoned hut. That's odd, because if Astrid's original statements are true, there's a chance players could end up with the contract on their heads and let the character go. Given the seriousness of the situation, her careless behavior made no sense.
This quest, like choosing Faendal or Sven in Skyrim, leading many players to infer that Astrid is lying to the player. In fact, it is possible that none of the victims signed a contract with them, and that each of them might have indeed signed a contract—but it is impossible to prove or disprove both hypotheses. However, as Camelworks explains in a YouTube video, she's actually telling the truth: there is a person who does hold the contract, but not in the way players think.
It's Possible Astrid Holds The Dark Brotherhood Contract In Skyrim

Interestingly, one theory is that Astrid herself actually holds the contract in the room. If the player decides not to play her game and kills her, her last words will be "well done". It could be her way of accepting defeat and praising the Dragonborn's legendary skills in Skyrim, but it could also be a hint that they cracked the case and she was the right target after all. In retrospect, she worded it rather carefully, saying that people with contracts should not have left the cabin — but Astrid could of course have fallen under that umbrella, too.
However, there is a big hole in this assumption. Since the Dark Brotherhood fell apart During the events of The Elder Scrolls IV: Forgotten, the members found in Skyrim are the last of all Tamriel. Considering that Astrid is the leader of the group, it is unlikely that she will accept a contract that is not favorable to her. It also doesn't make sense for the citizens of Skyrim to have her perform the Black Sacrament, as they'll likely be aware of her position of influence within Skyrim's Dark Brotherhood, which has pros and cons in the context of the game.
In a specific and borderline absurd set of circumstances, Astrid could be the one to contract. Similar to the three captives, though, players have little to no information to confirm or deny this theory. This seems to be the end of the trail. However, there's actually one more character that can be found in the Abandoned Shack, and unlike the others, there's concrete evidence that they're under a Dark Brotherhood contract. That role is the player himself.
Skyrim's Dragonborn Has A Dark Brotherhood Contract On Them

As explained by Camelworks, from the moment a player steps out of a Helgen Keep, their life expires. as long as they haven't joined the dark In the Brotherhood of Skyrim, one of the Order's Assassins randomly appears to attempt to take out the Dragonborn. The actual written contract can actually be looted from characters' bodies after they've been defeated in battle - and this malicious note was signed by Astrid herself. Not only did she know about the contract, but she was the one who sent the assassins on their (unsuccessful) missions.
In Skyrim's infamous prologue, the player is even hinted at being captured crossing the border to Hammerfell. According to Elder Scrolls lore, Hammerfell was the first region to sever ties with the Dark Brotherhood. It's possible that the Dragonborn, knowing the contract on their heads, decided to seek refuge in a safer area but were caught by the Empire, which could change Elder Scrolls 6. It's unclear why players would be wanted as part of the game before the event, but it would certainly explain why they'd be attacked by assassins, even before they'd done anything significant in the game.
Unlike the three hostages, or even Astrid herself, the player is the only one in the Dark Brotherhood Confirm that the start-up sequence of the contract is present on the header. Astrid knows this, but instead of killing them, she invites them to murder a (probably innocent) civilian or two. Her intentions are muddled, but given her rebellious nature at the end of the Dark Brotherhood storyline, we can only speculate on what she might really be planning in this ridiculous and mysterious Skyrim quest.
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