I thought the first hour of this movie was great. Stephen McHattie (WHATEVER HAPPENED TO ROSEMARY'S BABY, 300) portrays grizzled radio host Grant Mazzy. He works at a small station in the town of Pontypool, Ontario. The only other people there is a technician and his female producer, Sydney, who he butts heads with.
That particular morning there is a heavy snowstorm and they think their main job will be to report the various school closings. However, they soon start getting reports of people having seizures and attacking people. They get a particularly chilling commentary by their weatherman who witnesses a crowd of these crazed people and a building exploding. He takes cover in a grain silo and reports what he sees-- until he starts acting strange. It's some kind of virus. This virus is spread by the English language and certain words trigger it. The technician becomes infected and Grant and Sydney lock themselves in the sound booth while she bashes her head against the glass. A doctor breaks into the station and he explains to them what is happening.
Then they figure that the only way to keep from getting the virus is to switch the meanings of words around. At this point the movie kind of lost me as I just couldn't buy this virus being spread through the airwaves scenario. Yes, this is yet another variation on the pseudo-zombie scenario but it doesn't quite work well enough.