After being saved from choking on a nut at the party during The Gilded Cage story mission, the player can find Algernon at his greenhouse in Saint Denis and initiate the first part of the mission by talking to him.
There are a total of 6 parts for this mission. Each part has you collecting various exotic plants and animals for Algernon.
Note: This stranger mission can take a while to complete, so to complete faster be sure to collect the bird plumes and alligator eggs first.
Part 1 - Simply talk to Algernon and he will give you the first list of items that he will need.
Part 2 - Towards the end of the cutscene, Algernon mentions that he needs 15 Egret plumes and 15 orchids. Once the cutscene ends, inspecting the list reveals that Algernon needs:
All of which can be found in Bayou Nwa.
Part 3 - Upon returning to Algernon, Arthur is given a second list of items. These include:
- 20 Heron Plumes (found in Bayou Nwa)
- 7 Lady Slipper Orchid (found in Big Valley)
- 10 Moccasin Orchid (found in Roanoke Ridge)
Part 4 - The third list of items include:
All can be found in and around Bayou Nwa.
Part 5 - You will need to find:
- 30 Spoonbill Plumes (found in Bayou Nwa)
- 10 Rat Tail Orchid (found in Bluewater Marsh and Bayou Nwa)
- 5 Spider Orchid (found in Bayou Nwa)
- 5 Night scented Orchid (found south of Braithwaite Manor)
Part 6 - For the final part of this mission, you will need to find:
- 5 Clam Shell Orchid (found east of Caliga Hall)
- 5 Queen's Orchid (found in Bayou Nwa)
- 10 Sparrow Egg Orchid (found in northern Roanoke Ridge near a Hermit location)
- 5 Dragon's Mouth Orchid (found in Grizzlies East)
Once you have returned the last items to Algernon, he will give the player an exotic hat and exotic revolver named Algernon's Revolver.
Completing this Stranger mission strand is associated with these trophies/achievements:
Complete 10 Stranger mission strands.
Complete one of the Collectible strands
Attain 100% Completion.