Nan and Ryan are back in NYC after living abroad for 12 years. Nan is starting her consulting business while Ryan is off working with diplomats. Nan is left to deal with a non-existent contractor and a house that is falling apart more and more each day. Ryan is pressuring her to start a family, but Nan is just not sure she is ready to.
Then one day Grayer X, Nan's old charge who is now 16 years old, shows up at her door late one night. Nan feeling guilty about leaving Grayer how she did - helps his younger brother Stilton with a boarding school interview - posing as his mother. Suddenly Nan is thrown back into the world of Mr & Mrs X - who are in the middle of a very public divorce.
Nan gets an offer to be a faulty development person at Grayer's private school. She walks into a group of snobby kids ganging up on a good teacher while trying to impress the school board members. Nan navigates the politics at the school while trying to play mother and father to Grayer & Stilton.
Nan reconnects with some high school friends as well and finds herself in the middle of Upper East side mother and their nannies. Memories of her previous times with Mrs. X and Grayer keep flashing before her eyes.
In between the charity balls and weekends in the Hamptons, Nan realizes that she might be ready to be a mom but to Grayer & Stilton - not her own kids.