Air raid defence in Canada: HAS of large operations map on North Eastern Quebec, Eastern Townships, WVRC personnel moving markers on it. Cut to MS of bilingual sign "Air raid warning signal - Signaux raid aériens". Close shots of uniformed women at telephones. Shots of "Air Raid Warning" flashing, of helmeted soldier talking into phone, of WVRC girls putting on gas respirators and helmets and proceeding with the job of moving markers on the large map.