In "The Sinking City 2," there are many tricky special achievements, and "Behind Every Box Seeker" is one of them. This achievement requires you to unlock all emergency supply boxes (excluding DLC) in a single playthrough. The main challenge lies in finding the keys to these supply boxes. To start, the first box is located at the reception desk in the annex building.
How to Unlock the 'Behind Every Box Seeker' Achievement in The Sinking City 2