The First Encounter: New Austin
The Strange Man and John Marston first meet during a Strangers task "I Know You". Strange Man tells John that he knows John, but Marston does not recall meeting the man before. The Strange Man asks the player to save the man's friend, who he knows as "being in danger of being unfaithful to his wife" in Thieves Landing. Upon arriving at Thieves Landing, John sees the friend of the Strage Man talking to a prostitute. It's at this point that the player can either choose to encourage the man to sleep with the prostitute and give him money or try to talk the man out of being unfaithful to his wife.
The Second Encounter: Nuevo Paraiso
The second time Strange Man and John Marston meet is in Nuevo Paraiso, Mexico. The Strange Man now asks John to go to a nearby chapel, where John encounters a nun, which in turn asks John to donate money to the poor. Here players can either rob the nun for $300 or donate money and lose $12.
The Third Encounter: West Elizabeth
The third and final time that the Strange Man and John Marston meet is in West Elizabeth, near John's ranch, The Beecher's Hope. John gets angry at the Strange Man for refusing to tell him who he is, and tells the man that he won't be responsible for his actions if he happens to lash out. The Strange Man ignores Marston and proceeds to talk about the place they were currently at, calling the place, that would later serve as John Marston's grave site "nice". John loses his patience and proceeds to shoot at the Strange Man three times before his pistol jams as he was about the fire the fourth shot. Despite the fact that John, the remarkably accurate shooter was standing just a few feet away from the man, all of John's bullets seemed to pass right through the Strange Man. Marston proceeds to yell "Damn You!" to the Strange Man, who replies with "Yes, many have!" and walks away.
There are many speculations about who the Strange Man could be. The most likely theory is that he is God himself. He knows exactly what people are doing at what time, and tries to protect his "friend" from sin. Later he sends John to a chapel, God's house. During their third encounter John fires three bullets (referring to the game's end where one bullet stands for Uncle, another one for Abigail, and one more for John himself, also the pistol jammed exactly when John wanted to fire one more shot which was supposed to be for Jack), and finally the reply "Yes, many have" might refer to a swear word "Goddamn!".
Possible Red Dead Revolver Appearance
In Red Dead Revolver during the fourth chapter, on a train heading towards Brimstone, Red Harlow encounters a man, who claims to be heading to Brimstone for a job at the local bank, whilst during the West Elizabeth encounter, the Strange Man states that he is an accountant. This man from Red Dead Revolver somewhat resembles the Strange Man and is dressed in a similar attire, however this is just a theory.
For more information see the Unnamed Man article.
Leading up to the release of Red Dead Redemption II, on September 6th, 2018, the official Rockstar Games twitter account started posting artworks of members of the protagonist Van der Linde gang. Among them was the artwork of the character named Josiah Trewlany, who's appearance was immediately recognized by the fans to be similar to the Strange Man. Trewlany is an older, black-haired man, with a moustache, seen in an expensive suit, sporting a top-hat. After the game came out, the character didn't appear to share any characteristics with the Strange Man.
- During the third encounter with the Strange Man near Beecher's Hope, the man tells John that the place they're currently at is a "fine spot". This location later serves as John's burial site.
- In an issue of Gamepro Magazine, a closer look at Red Dead Redemption was given. When asked about the Strange Man's quest, and whether the "man in the black top hat" represented God or Satan, Rockstar told the magazine that they could not tell if the Strange Man was God, Satan, or anything else.
- It is actually possible to kill the Strange Man. The player just has to shoot him before triggering the cutscene. Doing so will fail the mission.
- The player cannot kill him once the mission is complete.
- The Strange Man can be "killed" right after the second encounter. He will appear to have died and the body can be looted. Doing so does not affects the "I Know You" side missions in any way.
- If the player points a gun at him, he can pull out a Cattleman Revolver and shoot and kill the player. He may also run away while yelling at John.
- There is a picture of the Strange Man hanging in John and Abigail's bedroom at Beecher's Hope, directly over Jack's bed and above the piano in the living room. Another picture of him can be found in the Blackwater safe house just above the saloon.
- After the first encounter with him, players can point a gun at him and he will start to run. If he is hogtied, he will keep talking as if the situation were normal. However, pointing a gun at him is considered a crime and civilians will attempt to alert law enforcement.
- The Strange Man is the only character John meets within all three territories of the map.
- If the player attacks the Strange Man he will say things like, "You always were a nasty little orphan", "Come now, Marston", or "You haven't changed."
- As mentioned above, there is a possibility that the Strange Man appears in Red Dead Revolver, although it is unclear if it really is the same person.
- The Strange Man is similar to two other mysterious beings that appear in newer Rockstar titles. The other ones are a dog which appears in a Strangers & Freaks mission in Grand Theft Auto V, which leads Franklin Clinton to a man stuck in a tree after a parachuting accident and Anders Detling, a man found in Max Payne 3 who appears in several missions. In the three encounters we learn that Anders Detling lives the life that Max always wanted to live, which was taken away from him.
- A portrait of the Strange Man can be found behind the counter in the general store in Armadillo in Red Dead Redemption 2. the player can interact with the picture, which leads to John asking Herbert Moon who is portrayed there. Moon responds saying that he is not sure, and that someone gifted the portrait and he thought it looked nice. Moon then asks John why they asked him and he responds saying that he thought the man looked familiar. This strengthens the theory that the man is, indeed, Josiah Trewlany.