Gabriel [the player character] is required to impersonate another man, Detective Mosely, and take his motorcycle rental. ... Although Mosely does not have a mustache, one of the requirements of the puzzle is nonetheless to create a fake mustache using cat hair. ... Gabriel must also steal Mosely's passport to use as ID. ... However, because Gabriel is now using a fake mustache to impersonate someone who does not have a mustache, Gabriel must use a magic marker to draw a mustache onto Mosely's passport photo.
Oh my.
I remember playing this game back in the day and getting stuck on this exact puzzle for over a week before I gave up and never touched the game again. It's nice to finally know the solution, but damn, I never would have figured that out.
Oh my.