Aspiring writer Hannah Horvath is left floundering when her parents stop supporting her financially; Marnie is beginning to feel suffocated by her long-term boyfriend; bohemian friend Jessa has just returned from travelling.

Hannah decides to get an STI test; Shoshanna reveals a secret.

Hannah finds out she has a sexually transmitted disease, and her honourable intentions to inform an ex-boyfriend prompt the dropping of another bombshell; Marnie is attracted to a cocky artist; Jessa gets a babysitting job.

Hannah is uncomfortable around her touchy-feely new boss; Shoshanna continues her quest to lose her virginity; trouble brews when Hannah's diary falls into the wrong hands.

Hannah propositions her boss; Adam has a different idea about his relationship with Hannah; Marnie and Charlie assess their relationship; Jessa is determined to conquer someone she used to date.

Hannah flies to Michigan for her parents' 30th anniversary celebration; Hannah spends time with old friends.