What annual Austrian society event which takes place in the building of Vienna State Opera in Vienna was featured in the made-for-TV movie Opernball?
Opernball (film): Opernball "(Opera Ball)" is a 1998 made-for-TV movie by Urs Egger based on a 1995 novel by Austrian writer Josef Haslinger in which thousands of people are killed in a Neo-Nazi terrorist attack taking place during the Vienna Opera Ball. Vienna Opera Ball: The Vienna Opera Ball (German: "Wiener Opernball") is an annual Austrian society event which takes place in the building of the Vienna State Opera in Vienna, Austria on the Thursday preceding Ash Wednesday (a religious holiday).
The Vienna Opera Ball