Hannah struggles to achieve her dream of becoming a successful writer in the wake of being cut off financially by her parents. Fortunately, she has three close friends for support—Marnie, Jessa, and Shoshanna.

Hannah forges ahead in her writing career and begins seeing someone new, but her enthusiasm is tempered by the responsibility she feels for her now-ex Adam—convalescing after his accident—and the pressures of the publishing business. Meanwhile, Jessa, Marnie and Shoshanna make strides in their own relationships and jobs, though the bumps they encounter remind them that they still have a lot to learn.

Hannah is in a committed relationship with Adam, with both settling into newfound domesticity in Hannah's apartment...but she's still a volatile mess of anxieties, insecurities and uncertainty. As Hannah works to rehabilitate her writing career, Marnie adjusts to life after Charlie; newly single Shoshanna looks to balance partying and studying; and Jessa resurfaces to continue her streak of disrupting the lives of everyone around her.

Hannah leaves New York to attend the prestigious Iowa Writers' Workshop, while confronting uncertainty in her relationship with Adam. Meanwhile, Marnie pursues a music career while balancing her professional and romantic relationship with Desi; Shoshanna graduates and begins interviewing for jobs while sorting out her relationship with Ray; and Jessa is trying out sobriety through AA, though her ability to stir up drama remains undiminished.

Hannah Horvath has put her writing ambitions aside, continuing to work as a teacher alongside new boyfriend Fran—a relationship that her friends urge her not to screw up. Meanwhile, Marnie micro-manages her wedding, only to realize she needs more space—after the honeymoon; Jessa tries to stay on the straight and narrow while working towards becoming a therapist; and Shoshanna thrives in her new job in Japan.

Hannah is enjoying new success as she lands a plum writing assignment that could dramatically change the course of her life. Meanwhile, Marnie, now in a relationship with Ray, seeks to maintain her post-divorce independence; Jessa and Adam, now also a couple, embark on a creative project together; and Shoshanna lands on her feet at a marketing agency.