After "The Gilded Cage", Arthur will receive a letter from Henri Lemieux, mayor of Saint Denis. In the letter, Lemieux mentions that Arthur robbed him and would like to meet back at his mansion at night.
Upon arriving at the mansion, Lemieux makes it clear that he knows who the protagonist is and that he was robbed during the party. Lemieux tells him that he has a collection of paintings that are to be viewed at an art gallery and that a professor is claiming that the works are fake. At the end of the conversation, Lemieux tells him to go to the gallery and have a word with Professor Shiftacre.
After arriving at the gallery, the professor can be seen exiting the building and will have to be followed into a secluded alley. Once in the alley, confront the professor by either threatening or beating him.
Either choice will have the professor agreeing to change his opinion about the mayor's paintings and have the player leaving the alley to meet with the mayor's assistant, Jean-Marc, back on the main street.
After waiting a few days, a letter from the mayor will become available from at any post office saying to return to his mansion again at night.
The player is tasked with getting a newspaper man named Hector Fellowes to donate to the mayor's new public library. Jean-Marc will inform the protagonist that Hector can be met at one of the roads leading into Bayou Nwa in a red stagecoach.
After making it to the road, either board the coach as it's moving or "callout" to the driver to make it stop and then enter to talk with Hector. During the talk, Hector will call the mayor a crook to which the protagonist says that he is a real crook and will dangle the man out of the moving coach until he agrees to make a donation.
After returning to the mansion, the player will be met by the mayor who will give him an old field manual titled Farm, Field and Falconry and task him to go to Jean-Marc's house to stop him from potentially spreading "lies" about the mayor and the protagonist to the newspapers.
Upon reaching the house, Jean-Marc can be seen walking onto the porch about to enter his home. The player will confront him and knock him out in order to take him back to the mayor's mansion without being seen.
After reaching the mansion, follow the mayor into the backyard where he will tell the player to kill Jean-Marc.
- If Jean-Marc is killed:, a thank you letter will be received in a few days from Lemieux, and the player will get 10% off in all shops in Saint Denis. However, this will result in a minor Honor loss.
- If Jean-Marc is spared:, he will promise to never mention anything to the newspapers and run off into the distance (this will also result in a boost of the player's Honor). Wait a few days and there will be a letter from the new mayor waiting at the post office saying that Henri Lemieux has resigned from his position as Mayor of Saint Denis.
- Jean Marc Mercier (optional) - Can be killed by Arthur/John to prevent him from giving out information about Mayor Lemieux or the protagonist.
- John Marston can also do this mission, despite the large time gap and that the Mayor requested Arthur.
- The mayor's reward for helping him in the final part of the mission is acumulative. This means that if the player decides to murder Jean-Marc and restores his maximum honor afterwards, he shall have 50% of shop discounts due to his honor plus the 10% discount promised by the mayor, totalling 60% in all shops of Saint Denis.
- If the mission is available when breaking in by destroying and climbing through one of the mansion's windows, Lemieux will be in his office and can be aimed at and even killed by the player. Jean Marc can also be found inside, however, he can only be killed with throwables such as fire bottles, due to the player being unable to shoot him.
Completing this Stranger mission strand is associated with these trophies/achievements:
Reach maximum or minimum Honor level.
Complete 10 Stranger mission strands.
Attain 100% Completion.