<P>Carla Gugino</P>

Carla Gugino

CBS is turning the debut of its upcoming alien spooker Threshold into an event. Sources confirm that the network in an effort to distinguish Threshold from the other five sci-fi entries premiering this fall will air the show's season premiere as a two-hour movie. Threshold stars Carla Gugino (Karen Sisco) as a government agent investigating a UFO sighting in the Atlantic Ocean.