La Clef is a story driven riddle game, not too far away from series like Unlock or Exit at heart.
The book tell the tales of a fantasy world named Astolie. It is divided in different chapters where the riddles can be solved independently. Solving all riddles of a chapter give hint on solving a final riddle that will unlock the next chapter. The story is divided in 5 chapters with a final riddle once everything is solved.
The riddles revolve around graphical puzzles, word puzzles, and hidden hints. The game also includes an UV light to unveil hidden parts of the story or solutions to some chapters. Hints and riddle happen online via the Author's website and an active Discord community.
The authors claim the story takes about 50 hours to complete when playing with a group of 2-4 people.