The chapter starts at the top of the elevator where the Lady was at the end of the Hideaway. In this campaign, the Kid finds himself in the Lady's Residence, eventually finding a room with several statues of the Lady. After solving puzzles to find three missing statues, while fighting off the Shadow Children, he finds the Lady looking at herself in a mirror. The Lady is revealed to have a gruesome face, possibly explaining why she wears a mask. In the last room of the Residence, the Lady captures the Kid and transforms him into a Nome. He then finds his way to the Guest Area and then to the room with the sausage in Six's campaign. The chapter ends with the Kid standing by the sausage, indicating that it is him who Six eats. When the credits for the Secrets of the Maw roll, they are eventually shown on a television set, after which the screen shows a figure reminiscent of the Hanging Man.
Source: Wikipedia, "Little Nightmares", available under the CC-BY-SA License.