Sherlock Holmes Chapter One

This achievement is missable, and is earned for completing the side-case 'String Theory'. This achievement just requires completing the side case, but it is missable if you progress to the point of no return, as it isn't mandatory for story progress (would need to re-load an older save in this circumstance). It can be started by finding the poster outside the cathedral in Scadalio (image below - credit to PowerPyx). You need to have completed 'A Gilded Cage' main story case, or you won't be able to get this poster and accept the side-case.



For this achievement, you need to complete the side case. It's a pretty straightforward and quick one compared to others. Once you are ready to conclude the case after , head back to the musicians house. Return his property, use focus (RB) on the sheet music stand, and speak to the musician again to unlock the achievement.