Here is the full list of all 36 The Invisible Hours achievements.
Explore the entire Island
Find the secret workshop in the basement
Watch Edison play chess
Watch Bernhardt putting on makeup
Find the chemistry notes
Find the first Tesla Diary
Find the hats
Activate Following mode
Be walked through by a character
Watch all the scenes in chapter 1
Watch all the scenes in chapter 2
Watch all the scenes in chapter 3
Watch all the scenes in chapter 4
Discover who killed Tesla
Watch Vanderberg's murder
Watch Mundy's death
Watch Gustav's fall
Go to the hotel room
Find Lafcadio Boone's mask
Use the Spirit Radio
Watch Gustav for the entire game
Collect all the clues
Travel back in time with Flora
Watch Bernhardt and Mundy recite Shakespeare
Find all of Tesla's diaries
Find all the newspapers clips
Find old photos of all the characters
Find all the letters from the guests
Look through the telescope
Listen to the lullaby
Find Edison's food bowl
Try to bang the gong
Find the library receipt
Find the fox
Find Deadlight logo
Find the Ulysses poem