From NetFlix:

College-educated Annie Braddock (Scarlett Johansson) gets a crash course in child care when she plays nanny to the 4-year-old son of grossly dysfunctional parents (Laura Linney and Paul Giamatti). Directed by Shari Springer Berman (American Splendor), this all-star comedy was adapted from the best-selling novel by Emma McLaughlin and Nicola Kraus, who based their book on their experiences working for Manhattan’s wealthiest families.

Scarlett Johansson is a nanny for the son of unhappy, nasty rich New Yorker Laura Linney named Mrs. X. It’s a B-film with a happy ending. I could not really find anything wrong with this movie (slightly preachy climax). Paul Giamatti is Mr. X.