Ten year old Mathilde (Louisa Pili) lives with her mother Helene (Sandrine Bonnaire) in a suburb of Paris. Her only other family is a telephone dad (living in America with a new partner) and her grandfather Paul (Claude Rich), a retired bookseller, whom she and her mother visit regularly in his nursing home. Unknown to all she has found a cache of letters hidden by her gramps and written by her maternal grandmother Madeleine (Monique Mélinand) to Helene (and one to herself - the only one she's opened). Paul has taken bitter revenge on his wife for having left him, with his best friend, when Helene was ten; but he has deceived and embittered his own daughter in the process. As a result Helene hates her mother. Mathilde becomes a catalyst to put things right. She leaves home in the dead of night, walks to her gramps' and confronts him re the letters. He agrees to try to find his ex-wife and they head for the address on the letter sent when Mathilde was born. (His absence in the nursing ...