Holly Barker and her husband, Jake, were third in line at the Louvre the morning of Oct. 19.

The couple from Indianapolis had a plan ¡ª head straight for the Mona Lisa, before the crowds, then shoot toward Delacroix¡¯s ¡°Liberty Leading the People¡± and a famous painting of Napoleon by Jacques-Louis David. Fourth stop was a place they had heard was a mini version of Versailles¡¯ Hall of Mirrors: the Apollo Gallery, with its collection of royal jewels.

It was 9:32 when Holly Barker stepped inside the gilded hall and took a photo. As she stopped to admire a wedding gift that Napoleon had given his second wife ¡ª a necklace glittering with 32 emeralds and more than 1,100 diamonds ¡ª she heard the first of three loud bangs. It was 9:34, and masked thieves were about to barge through the window.