VIDEO : James Corden Gets Duped by Katie Couric on April Fools' 'Late, Late Show'

The Late, Late Show with James Corden celebrated its inaugural April?s Fools Day Wednesday, and his guests rose to the occasion. Yahoo global news anchor Katie Couric paid her first visit to Corden?s new show, where she staged an elaborate prank that turned the new late night host white as a sheet and caused him to let several expletives slip. Couric employed a convincing stunt double ? dressed in the same outfit and all ? to make Corden believe she had taken a nasty fall down the stairs on her way to the stage.??