From publisher blurb:
This short guided adventure for The Legacy of Cthulhu was designed to serve as an example to players new to narrative games on how to start telling their own stories. Symphony of Madness presents a simple tale with a linear structure. It was written for someone playing Solo using a main character and 3 NPCs, but you can adapt it to play cooperatively or with a DM.
As you play, we highly encourage you to reference the core book to add your own touch to your adventure, picking events, adding checks, choosing items, or other elements that might fit your tastes. It is your story, after all.
In Symphony of Madness, Survivors hear a sinister sound echoing from somewhere in the Tile where their Shelter is located, which causes even the sanest minds to experience a sudden and violent surge of madness.
To remain sane and save their friends, the Survivors must find the sound's source and end it.