Plan Maggie (Greta Gerwig) to have a child on your own is derailed when she falls in love with John (Ethan Hawke), a married man by destroying his marriage volatile along with Georgette (Julianne Moore), seems brilliant and impossible. But after three years and a daughter, Maggie is a new dilemma: what do you do when you suspect that a man and his wife are in fact ex perfect for each other? …