VIDEO : ?Frozen? Stars Kristen Bell and Josh Gad Surprise Disney Fans at D23 Expo

Kristen Bell, who wowed fans as Anna in ?Frozen,? surprised fans at D23 Expo in Anaheim to present the upcoming ?Frozen? short film, ?Olaf?s Frozen Adventure.? The 21-minute film follows Olaf, Anna and Elsa during the holiday season, as Arendelle is left empty while villagers head home to spend time with their families. When Anna and Elsa tell Olaf that their family has no family traditions of their own, Olaf goes door-to-door asking other families how they spend the holidays.