Re-posting this from a thread on the old forums.

Summary:

The player is sent to "remind" a taxpayer who's late with his taxes to pay them. When the player gets to the taxpayer's house, he turns out to be dead. The player is framed for murder, and now needs to find more evidence to clear their name.

From here, there are two alternate ways we could take this:

A: The taxpayer is an outlander who got involved in smuggling ash statues. In the process of doing so, he met a REAL Sixth House cultist, and was murdered. The player finds fragments of his journal in a Sixth House dungeon, which can be used to clear their name.

B: The taxpayer is a Dunmer who became a Sleeper, and staged his death so he could escape to worshipping Dagoth Ur without any ties to his previous life. The player meets up with the Dunmer, who offers to clear the player's name with sufficient evidence if they promise to go away and leave them alone.