Walk-in Theater is a portable virtual cinema for the display of spatially distributed multichannel movies (“walkies”). The miniature experience engages participants’ proprioceptors and spatial memory, allowing them to orient themselves as they navigate a field of scattered video streams and localized sounds reproduced on a handheld computing device. Departing from one-way linear cinema played on a single rectangular screen, this multichannel virtual environment pursues a cinematic paradigm that undoes habitual ways of framing things, employing architectural concepts in a polylinear-video polyphonic-sound construction to create a kind of experience that lets the world reveal itself and permits discovery on the part of beholders. Interaction design for Walk-in Theater supports approaches to cinematic construction that employ the ambulatory, multiple and simultaneous viewpoints that humans exercise in everyday life.