Maggie (Greta Gerwig) is a New Yorker. Like most women working here, she is independent, confident, energetic, and gives people a fresh feeling. In this fast-paced big city, it is too difficult to find true love, so Maggie decided to skip this step and rely on artificial insemination to get a child of her own. However, just as Maggie was about to undergo surgery, a man named John (Ethan Hawke) broke into her life. The gentle and knowledgeable John soon made Maggie's heart move. However, John has a wife, Georgie (Julianne Moore), who has a very bad relationship with him, and a very strange relationship quickly formed between the three of them.