Billed as a “dramatic interactive theatre experience”, The Hidden already sounds intriguing – is it a show, a theatre tour, an audience participation play? Cleverly, it’s not actually made clear even after our small group arrive at Edinburgh’s Central Library and are shown where to wait.

Right on time, we are greeted and led, not to a theatre, but to a quiet table in the lower levels of the building. Here, we are gathered and greeted by librarian Alice, who introduces herself and begins delivering a Powerpoint presentation focusing on the history of the library. It’s pleasant enough but some of us are wondering whether or not we’ve signed up to the wrong event. But just as the sinking feeling descends, things go awry and we realise all is not as it seems.

After being successfully hoodwinked, the group is presented with a missing person backstory and are implored to piece together clues and investigate the disappearance with the help of Alice. The bulk of the event then takes place in the library’s main hall as we split into sub-groups and rifle through the shelves following a trail of research and riddles. It’s essentially an escape room-style activity, but The Hidden has the edge with a fantastically crafty lead actress – Veronica Leer – and the atmospheric surroundings of an actual library. We’re also not merely cracking a series of arbitrary number and picture puzzles. Theatre company Visible Fictions attempt to create a narrative that relies on what we’re uncovering in the books and requires participants to actually read excerpts of prose as well as decipher codes. The necessary teamwork is enjoyable and towards the conclusion we all gather together to share our findings and discuss our theories.

The story isn’t pieced together perfectly and we have to be helped along by Leer at points. But the journey is entertaining and the make-believe good fun. It results in a finale that most will find satisfactory, if not watertight. Moreover, the creators are presenting us with a message to take away. Without spoilers, The Hidden is a reminder and champion of the importance of libraries and the written word. Pretty noble for an interactive game!