When the script for Lourdes (2009) first landed on Sylvie Testud's desk, her initial reaction was that she didn't want to do anything that might involve her playing a nun or taking easy potshots at religion. She instantly changed her mind after reading the script.
The extras in the film really were pilgrims to Lourdes.
In late 2008 it was reported that Valeria Bruni Tedeschi had been cast in the role of Christine. Some time later she dropped out and was replaced by Sylvie Testud, who had already met with the director before Bruni Tedeschi was considered.