Canada has adopted stricter immigration policies within the last thirty years, which criminalize forced migrants. This has resulted in the construction of immigration holding centers (IHCs), buildings built exclusively for the detainment of undocumented individuals. As part of a directed design studio research project, the Laval IHC in Quebec, Canada, was examined by reconstructing government-issued design guidelines obtained using public access to information requests. The resultant project employs architectural documents as evidence to rebuild the interior spaces of the building through conventional tools of architectural representation, such as drawing, photography, and physical and computer modeling. By unveiling architectures shrouded in secrecy, this article illustrates how the design of these infrastructures legitimizes the narrative that undocumented migrants are “illegal” and should be incarcerated.