You are playing as 2 persons. Mark and Simon. You will be able to change between these characters... and others...
A gem in amnesia, this mod (and part 2) feature some really cool elements that have never been done before in amnesia (no spoilers) There is also a solid story and good puzzles. The only reason i don't giver this a 10 is because
1. Got stuck way to may times not knowing what to do
2. Almost no scares
still a great refreshing twist on amnesia and i recommend trying it