An accordion-style storm shutter panel and system for use in covering an opening in a building structure including an outer frame assembly and a plurality of vertically mounted elongated panels foldably connected together in accordion style fashion. The panels are joined by slip fitted lateral knuckle joints and a track engaging a guide which extends from ends of the knuckle joints. A plurality of spaced apertures are formed through and extend over the substantial length of each of the panels, each of said apertures preferably having a notch-and-tab arrangement extending around a periphery thereof. A plurality of transparent, translucent or opaque locking plugs are sized and have a spaced locking tab arrangement around a periphery thereof, which matably and releasably lockingly engages within each aperture. Alternately, the plugs may be fixed in place and be light-transmitting.