Oblivion - Dark Brotherhood Quest 1 - A Knife in the Dark

According to the rumor mills around Cyrodiil, the Dark Brotherhood comes to you in your sleep after you murder someone to recruit you. This is, in fact, true. To be invited to the Brotherhood, you must murder someone in cold blood. In other words, you must murder an innocent without provocation (note that Bandits and the like do not count as the required murder). Once the deed is done, regardless of who is there, the cryptic message "Your killing has been observed by forces unknown..." will appear in the corner of your screen, indicating you will be visited the next time you sleep. For suggestions on who exactly to murder, consult this guide.

Once your murderous actions have been "observed by forces unknown," sleep at any rest area to be contacted by a Dark Brotherhood's Speaker, Lucien Lachance. To prove your worth before you join the Brotherhood, you must kill Rufio, an old man attempting to hide from his past at the Inn of Ill Omen, located north of Bravil on the Green Road. Upon accepting the quest Lachance will give you a dagger known as Blade of Woe, an unenchanted dagger that remains a quest item until the final Dark Brotherhood quest.

Speak with the Innkeeper at the Inn to discover that Rufio lives in the basement of the Inn and is quite the recluse, never emerging. Entering his room is easy enough; enter through the hatch to the basement. Rufio's room is on the left at the very end of the corridor and the door is not locked. Killing him is quite easy; if he is sleeping, punching him once will do the trick. It is advisable to not use magic, as someone may hear the blast and come rushing downstairs.

If you speak with him before you kill him, he makes vague references to a horrific event in his past, and it is implied that he was part of an attempted rape that resulted in the death of the victim. This is later confirmed if you investigate the backstory of Claudius Arcadia, who arranged Rufio's assassination as retribution for killing his wife or daughter.

After you kill Rufio, you can actually just sleep in the (now dead) man's bed, although any bed will do. Regardless of where you sleep, Lucien will reappear and welcome you into the "family".

He will send you to the Brotherhood's main safe-haven, hidden in an abandoned house in the eastern part of Cheydinhal. When you come across the 'Abandoned House' (there is an easy lock on the boarded-up door) and make your way through the basement, you will see a door with red light emitting out of it. Activate the door, and when it asks for a password, answer 'Sanguine, my brother' just as Lucien instructed.

Once inside the Dark Brotherhood Sanctuary, you meet your new family led by the Argonian, Ocheeva. Ocheeva will give you your reward for joining the Dark Brotherhood, a Shrouded Hood and Shrouded Armor, two pieces of armor with benefits to stealth-based skills. Since you are a new family member, you must start out with "less important" contracts until you prove yourself. Your new brother who is responsible for handing these contracts out, Vicente Valtieri, just happens to be a vampire. He offers you a chance to become a vampire, or "hunter of the night" as he puts it, if you can prove yourself worthy to be one.

You will now be given a series of missions that involve assassinating people, in the form of 'Contracts'. Once Vicente gives you the first it will conclude this Quest, and begin the first chapter in your long, shadowed, twisted descent into the void with A Watery Grave.