The Big C is a comedy drama that revolves around a woman who’s inflicted with a pernicious disease. Cathy Jamison (Laura Linney) is the female protagonist who has been diagnosed with cancer.
Having realized that she does not have much time in hand, the lady decides to utilize the time in putting the life of her family members on track. Thus she tries to keep the news about her fatal disease under wraps and decides to take on life albeit in a different way.

Cathy’s household is inhabited by a set of slightly quirky characters. Paul (Oliver Platt) is her husband who doesn’t accept challenges straight on the face. His kid-like notions often mar his thought process. He even cheats on his wife transgressing the very boundary of marital institution. Adam (Gabriel Basso) is Paul and Cathy’s son. He’s a teenager juggling with some of the usual problems one encounters at this stage. Physical intimacy with one of his classmates, Andrea followed by infamy when this affair becomes public, pushes him in further dilemma. Cathy’s heartfelt desire is that her hubby and son accept the realities of life so that they gear up to face the unanticipated vacuum that would crop up later on.

Some other ancillary characters also play pivotal roles that carry the story forward. Marlene (Phyllis Somerville) is a neighbor and a close friend of Cathy. She’s also Cathy’s confidant with whom Cathy first unburdens the brutal reality that she won’t live for long. Dr. Todd Mauer (Reid Scott) is the oncologist to whom Cathy approaches for treatment. Both strike a good rapport with each other and soon the doctor realizes that what he feels is more than usual concern for Cathy. Successive episodes of the series witness the much suppressed fact about Cathy battling for life becoming known to her near and dear ones. Cathy opts for treatment after sending jolts through the lives of those who matter the most to her.