Knock knock Key

There is an unusual cottage in the depths of the forest.
It has been used as a laboratory and home for three generations by the Lodgers.
But lately, the last Lodger has noticed strange changes in familiar surroundings; things are missing, noises and noises are heard. Something strange is coming out of the forest. When night comes, it looks like someone has made their home in the dim light of rooms, attics and cellars.

You need to stay awake and healthy until dawn.
The tenant walks through the rooms, avoiding the unknown, counting the minutes until morning.
But only during the night can he solve the main puzzle and find the answers.