The Vatican, however, revealed some details of his final day as pope, saying he would attend a morning farewell ceremony with his cardinals and then fly off by helicopter at 5 p.m. to the papal summer retreat at Castel Gandolfo.

NPR: Pope Celebrates Last Public Mass As Pontiff

Mr. Lagerfeld was also one of the first to learn of Ms. Kruger's role as Marie Antoinette in "Farewell, My Queen, " a new film about the Franco-Austrian queen's final three days in the court of Versailles.

WSJ: Diane Kruger | 20 Odd Questions