What moves between the walls of our public buildings? Who is it that truly inhabits these spaces? And what roles do we play within them? What if we are both the building blocks and the inhabitants, the creators and the created? What if we write the script as we go along?This book stems from a two-day performative symposium, Unknown Grounds: The Public Building which brought together artists and thinkers to immerse in speculative scenarios.By borrowing tools from the performance arts, we explored embodied collective thinking around the notion of "the public building." We became characters in an experimental play, exploring new ways to relate and engage. In the shelter of fiction, we were free from social habits, empowered to see ourselves not just as passive occupants, but as active architects, speculators, constructors, foundation inspectors, janitors and maintenance workers. Script for a Synthetic Play: The Public Building features texts by Hamja Ahsan, Lila Athanasiadou, Nina Glockner, Ribal al-Khatib, Anna Moreno, Flora Reznik, Nishant Shah, and Eef Veldkamp. These contributions were shared before the event of the symposium, providing a virtual prelude to the conversations that unfolded and invited readers to co-create a communal space even before stepping into it. It also includes a fictionalized wrap-up discussion presented as a script, offering a fresh take on the ancient Greek comedy genre, drawing from its capacity to create a space for democratic, critical reflection on our political systems. In the same spirit, we now invite readers to share the virtual space of thought that this book opens. It serves as both an archive and a prompt, encouraging us to navigate the unknown and imagine new ways of collectively inhabiting and reshaping the public realm.