City Hall’s impenetrable walls, deep shadows, and scale-less monumentality can seem intimidating, obscuring any sense of how the building is to be entered or used, but the same can be said of Roman ruins or mediæval castles, structures that we consider inspirations. The competition-winning design from Kallmann and McKinnell was hailed as a masterpiece when completed in 1968; like Frank Gehry’s Bilbao Guggenheim Museum, it touched the spirit and defined a time and place. Times change, and buildings have to change too, but as ArchitectureBoston editor Elizabeth Padjen puts it in the October issue, “Boston doesn’t have to build a new city hall in order to get a new city hall.”

All the architects at Pinkcomma take the ruin-like quality of the building as a starting point, reinhabiting the plaza and its towering concrete colonnades with new constructions that bring in light, color, and clarity. Höweler + Yoon Architecture wraps the building with an elevated walkway that extends the plaza up over the roof and then penetrates the structure with public pathways to define entry and interior circulation. Kuo.Chaouni with Uenal Karamuk strips away the building’s massive brick base to allow the plaza to continue through to Congress Street, creating transparency and connection. Single Speed Design uses landscaping to tie Boston Common to City Hall Plaza, Quincy Market, and the Greenway beyond, adding a sunken garden off Cambridge Street to connect to T lines below.

Studio Luz Architects with C2 Studio Landscape Architects introduce new uses — a hotel on top, stores and cafés in the base, and a water-filled plaza that can be used for year-round recreation. Over,under adds an extensive network of canopies, an enclosure over the interior courtyard, and new glass-wrapped retail space on Congress Street and removes the cascading stairs inside to open up the interior.

Pinkcomma is a labor of love — an extension of Over,under’s multi-disciplinary approach to design that directors Mark Pasnik and Chris Grimley run out of the front of their studio. What makes their show work is the strong point of view and the conviction that architecture, urbanism, and design deserve to be explored in depth.