Woh Saat Din opens with the wedding of Maya and Anand. On their wedding night Anand finds out that Maya has consumed poison since she was forced into the marriage by her parents. Anand, who is a doctor is able to save Maya and asks her what is troubling her. He promises to fix her problem or to help her in any way possible. Maya tells Anand about her erstwhile relationship with Prem.
Prem Prasad Patialawala is a struggling musician who has come to Mumbai with dreams of working in the Hindi film industry as a music director. He is accompanied by a teenager named Chottu. While scouring the city for a place to stay, they come across a house that has a room on rent. The house belongs to Maya’s grandfather.
Maya lives in the house with her mother, her younger sister and brother, since her father abandoned the family. Prem rents the room with Chottu and soon settles in. Over time, Maya forms a close bond with Prem. Due to his financial condition, he brushes off her advances towards him. Eventually he gives in and they fall in love. When her family finds out about it, Prem is beaten and sent away while Maya is married off to Anand.
Anand, a widower agrees to marry Maya since his mother who is a terminally ill patient wishes to see her son get married to someone so that she can look after his daughter, Chanda. Anand’s mother, Savitri has only a week to live. Anand convinces Maya that he will re-unite her with Prem once his mother passes away, so that she can die in peace.
Meanwhile, Maya becomes close to Chanda, Anand’s daughter. Anand, on the other hand, comes across Prem while wandering the streets. He poses as a movie producer and offers Prem a job as a music director for an upcoming film, so that he can keep Prem close to him and reunite him with Maya when the time is right.
When Anand’s mother passes away, he finally reunites Prem and Maya. But Maya refuses to leave Anand, having realized the strength of the institution of marriage. Prem agrees, since he does not want to violate the sacred bond of marriage. Leaving the couple to build their own life, Prem leaves on his own journey.