A break-in resistant window assembly whose components include a pane having at least a pair of edges and a corner; a frame boarding the pane; a sheet of polymeric film overlying the pane, a first adhesive layer fixedly interconnecting the pane and the sheet of polymeric film; a corner piece having a pair of legs; a pair of trim engaging lugs fixedly attached to the legs' distal ends; a first adhesive pads attaching the corner piece to the frame and attaching the corner piece to the sheet of polymeric film; a pair of trim pieces having proximal end openings receiving the trim engaging lugs; and a plurality of second adhesive pads attaching the trim pieces to the frame and to the sheet of polymeric film.