This was the most successful French movie in the Netherlands, due to the popularity of the book on which this movie was based, until The Intouchables (2011) took the record.
This is the second of three movies about World War II in which Dame Kristin Scott Thomas appeared. The others being The English Patient (1996) and Suite Française (2014).
When Édouard Tezac and Julia are in the car he tells her the story of the day the girl came back to the apartment. He mentions that there was a dead cat in the kitchen when they moved in.
After Sarah and her father are walking to the bus to the Velodrome d'Hiver, the wall where Michel Starzynski is locked in the closet is shown. He asks "Sarah, are you there?" as a cat is seen leaving the room.