She withholds the diagnosis from her immature husband Paul (Oliver Platt), homeless brother Sean (John Benjamin Hickey), and delinquent son Adam (Gabriel Basso).

Her cranky neighbor Marlene (Phyllis Somerville) opposes the project but ultimately begins to bond with Cathy and becomes the first person to learn about her cancer.

Cathy also begins exhibiting increasingly odd behavior in reaction to her cancer, such as emptying out her retirement fund and burning the couch she's always hated.

Seeking direction in the wake their new leases on life, Cathy and Paul attend a retreat by a self-help guru named Joy Kleinman (Susan Sarandon).

While scuba diving in Puerto Rico, Cathy experiences a vivid hallucination caused by the growing tumors and requires brain surgery.

Her relationship with Paul is cordial although she suspects that he's waiting for her to die to move on; Cathy in turn encourages him to begin dating other women so she can approve of who he may remarry.

Per the advice of a counselor, Cathy sets a goal that she wants to see Adam graduate high school before she dies, although this appears unlikely considering he's only starting junior year.

[7] Alessandra Stanley of The New York Times wrote: "The Big C works because most of the writing is strong and believable, and so is Ms. Linney, who rarely sounds a false note and here has perfect pitch... the series is at its best when sardonic and subdued.

"[8] Washington Post critic Hank Stuever said: "Buoyed by scalpel-sharp writing and even keener performances, The Big C ...walks a fine line of having it both ways.

[11] Maureen Ryan of AOL TV stated that "Having a character and her family deal with a potentially fatal illness is such a rich arena for both drama and black comedy, but so far, The Big C hasn't been able to mine that topic with consistent freshness and depth.

"[12] Ken Tucker of Entertainment Weekly was critical towards the show, but commended the acting, stating that "Much of The Big C's unoriginal dramatization of cancer concerns is mitigated by the fresh, dynamic performances of Laura Linney and Oliver Platt.