Look for the guard captain
Among your contracts is something personal. The guard captain of Denerim apparently wronged Marjolaine somehow and she wants revenge. She is taking care of it herself. It will be interesting to see what she cooks up.
Pity the man, whatever comes.
Acquisition
You start out with the quest in your journal at the very beginning of the campaign.
Walkthrough
This quest is affected by the other quests that you partake in the Market. Each sub quest yields an item which can be used to further incriminate the Denerim City Guard Captain. Guard Captain Eams can be found unconscious on the street just past the Gnawed Noble Tavern.
Once the item has been obtained, place it on Eams.
Three items can be obtained from Stealing in the Market:
Result
Placing all the items (save the mage's ring) upon his person will unlock the Vendetta achievement and Marjolaine will compliment you.