The world of Red Dead Redemption 2 isn't just filled with crooked individuals and dangerous outlaws. During the course of his journey, Arthur will meet many who have devoted their lives to helping people and doing good deeds whenever possible. Among them is a person Arthur can meet in Rhodes, Dr. Alphonse Renaud, the main character of the No Good Deed Stranger Mission.
The No Good Deed mission can be started at any time from Chapter 3 onward by talking with Dr. Alphonse Renaud, who is sitting in front of the Churchyard in Rhodes. By talking with him, Arthur will learn that the doctor's wagon, including his medical supplies, has been stolen by some no-good thieves. Never turning down a plea for help, Arthur sets out to recover the stolen wagon.
Once you are done talking with the doctor, the location of the wagon will be marked on the map. It's not too far from Rhodes, just head to the northeast and stay close to the river.
Once inside the marked area, you will notice that there are six enemies guarding the wagon. You can deal with them any way you like: using a stealth approach and possibly killing the enemies with your bow may require a little bit more time, so you can just go inside the area, activate Dead Eye, and kill all of them.
Once that is done you can finally recover the wagon and head back to Rhodes. On the way back to town, you will be attacked by two more enemies on horse. Activate Dead Eye to get rid of them easily.
Ending and Rewards
Once you have back to Rhodes, Alphonse Renaud will thank Arthur profusely and give him a reward, the Special Health Cure Pamphlet, which teaches Arthur how to craft a Special Health Cure once the pamphlet has been read, by accessing his Satchel. The medicine needs 2 Ginseng plants, 2 Yarrows and 2 English Maces of Milkweed to be crafted at camp.