LOS ANGELES — In "The Big C," due Aug. 16 on Showtime, Laura Linney plays a teacher newly diagnosed with fatal cancer. It's a comedy.

Clips are indeed funny, showing Linney's Cathy living out all sorts of impulses, from burning the couch she hates to getting her first bikini wax.

The humor is fitting because "The Big C" isn't a show about dying, Linney told TV critics meeting Thursday. It's a show about living.

"She's a woman who doesn't really know who she is," Linney said. ""She's been functioning really well, but she hasn't been living. She has a huge growth spurt through this experience."

Linney is an executive producer of the series, created by Darlene Hunt. Jenny Bicks ("Sex and the City"), who'll run the show, is a cancer survivor.

Linney said that When she read creator Darlene Hunt's script, "What hit me the most was the theme of time. How much time do we get? It's a privilege to grow old." The series finds her "going on the journey with Cathy, actually," she said. "I'm at the age where relatives are growing older, friends are dying."

Hunt said that in handling Cathy's reaction to her cancer diagnosis, "We wanted to turn some expectations on their ear. What would be a knee-jerk reaction to just wanting to feel good and live life differently?"

Oliver Platt, who plays Linney's husband, wondered "why do we start to live beautifully when we get a death sentence?" He called the show very truthful, asking, "Who knows how someone is going to behave when they get this kind of proclamation on their life?"

"The Big C" joins dark comedies "Weeds," "Nurse Jackie" and "Californication" on Showtime.

Asked whether Cathy might wind up purchasing medical marijuana from Mary Louise Parker on "Weeds," Linney laughed and admitted that had been discussed. "I'd love for all the Showtime series to cross over," she said. "I'd love to go see Nurse Jackie and have an affair with David Duchovny" on "Californication."