On the eastern edge of the map, there is a little outpost called Van Horn Trading Post. It is found north of Saint Denis, which is in the southeastern corner of the map. You know you're in the right place when you see a lighthouse on the coast. The Stranger for this mission is located inside of the saloon, so go in there to find a woman and a deformed man near the bar. Greet the woman in order to begin this side mission.
After speaking about betrayal, you notice the big guy taking a hefty drink from a bottle at the bar. He'll have a little tussle with the bartender, with the bottle going flying, which leads to the big guy grabbing a hold of the bartender. The woman tries to stop Bertram to no avail, leading to her asking you to get him to let go. You will get into a fist fight with Bertram, so lock on with L2 and get brawling. Bertram isn't any different than a normal fist fight, so block with Square/X and punch (Circle/B) when you have an opening. If needed, consume a health tonic if your health runs low. Upon knocking down Bertram, you will finish the first part of this side mission.
The Smell of the Grease Paint - Part II
You learned that Magnifico, the other member of Miss Marjorie's little troupe, is camping somewhere in the woods, but not any general area. However, open up your map and look to the southwest of the Trading Post to see a map marker across the Kamassa River. It's south of the Kamassa River name on your map and just north of "Maclean's House." Approach the giant white circle there and look for a campfire, as that is where Magnifico will be camping.
As you get close to the campfire, Magnifico will strike up a conversation with you, then run off. Give chase after him, knowing that he will throw down some smoke bombs to lead you off his trail, but his location will always be revealed on your minimap. When you get to the river, he'll look like he disappeared, but he will actually be across the river. Continue the chase, keeping an eye on your minimap, only for three puffs of smoke to appear.
Investigate each one and the chase will start anew, with the trail going cold in a clearing shortly after the fact. You'll need to search the clearing for signs of Magnifico, although he'll reveal his location if you take too long. He is in a tree on the northern side of the highlighted area. He'll mock you, then continue playing his little game of cat and mouse, so resume the chase. You think you have him cornered with an oncoming train, but Magnifico evades you by appearing on the other side. Wait for the train to pass and run after Magnifico once more, only this time, it won't last long, as Marjorie and Bertram will ride up on their wagon.
With Bertram's help, Magnifico will rejoin the troupe and the side mission will end, although you don't get a reward for it. If you listened to Marjorie before she rode off, she said she'll give you some of the money from their next show in Saint Denis. Head to the theater there and tell the ticket taker you're her for Marjorie. You'll receive a free ticket to their show, so stay and watch it if you want. After it's over, return to the ticket taker to receive $40.00 and a Letter from Miss Marjorie, thanking you for your help.