Two mothers come together under strange circumstances in this drama that mines the mystery of reincarnation. Ariane's (Isabelle Huppert) son, Camille (Charles Berling), announces one day that he's actually Paul and needs to find his mother. Believing a supernatural force is driving this unusual request, Ariane takes him on faith and helps him find Isabella (Jeanne Balibar), a woman who lost her son, Paul, in a drowning accident.