The Shady Rest Inn quest chain can start either at the Inn itself, from the objects, or from Brackenwall Village (37.6,31.7), Dustwallow Marsh.
If the player chooses to start the quest chain in Brackenwall, Krog (36,31) will give the following quest:

1. Inspecting the Ruins

This quest completes at Inspector Tarem (29.6,47.5), located just outside of the inn, who will then use powder to help 'illuminate' the "clues." This basically causes purple arrows to appear, pointing at the individual quest objects strewn about the destroyed inn. Obtaining and completing this quest is not necessary, as the quest chains can be started directly from the objects regardless.

From the Shady Rest Inn (29.4,47.5), the quest branches into three paths, each starting when a different item gets looted.
The first quest for each chain will have you bring the three items to Krog in Brackenwall Village.

Loot the Black Shield (29.6,48.6):

1. The Black Shield
2. The Black Shield
3. The Black Shield
4. The Black Shield

Loot the Suspicious Hoofprints (29.7,47.7):

1. Suspicious Hoofprints

Loot the Theramore Guard Badge (29.8,48.2):

1. Lieutenant Paval Reethe You are here!
2. Questioning Reethe

After completing all three quest chains, Krog will offer a fifth The Black Shield quest, asking players to bring the Blackened Iron Shield to Mosarn (55.6,79.6) in Thunder Bluff.

Mosarn will then volunteer new information regarding the "mystery" and starts the following short chain:

1. Return to Krog
2. More Than Coincidence and The Grimtotem Plot

When these three quests have been completed, Krog will direct you to Tabetha (46.0,57.1) for further progression and conclusion:

1. Seek Out Tabetha
2. Raze Direhorn Post!
3. Justice Dispensed