Edie Falco stars as a cynical, painkiller-addicted nurse in the Showtime series Nurse Jackie. (Corus Entertainment/Movie Central)

Joan Didion’s 1970 novel Play It As It Lays features one of the more arresting opening sentences in modern fiction. Speaking from inside a mental hospital, Maria Wyeth, the jaded protagonist, declares, “What makes Iago evil? some people ask. I never ask.” When pressed by doctors to explain the reckless, despairing behaviour that brought her to the institution, Maria later replies: “I am what I am. To look for ‘reasons’ is beside the point.”

Nurse Jackie is first-rate, highly addictive television, thanks to the complex, deliciously subversive character at its centre.

A similar nihilism courses through the new Showtime drama Nurse Jackie. Don’t let her regulation blue scrubs fool you: Flinty, foul-mouthed Jackie Peyton (Edie Falco) is far from the selfless, Florence Nightingale nurses who usually appear on TV. In the pilot, we meet Jackie while Dionne Warwick’s wistful ode to pill popping, Theme from Valley of the Dolls, plays in the background. It’s a surreal sequence, and we see Jackie’s eyes go glassy as handfuls of red capsules gently rain down around her. After describing her morning pick-me-up of crushed Percoset — “just a little bump to get me going” — she sets about her typical day at New York’s All Saints hospital.

In Episode 1, Jackie makes a bang-on diagnosis, doles out maternal hugs to anxious folks in the waiting room and is called a “saint” by a student nurse named Zoey (Merritt Weaver). But in between moments of nurturing, Jackie finds time to lift cash from a rapist’s pocket, forge a signature on an organ donor’s card and flush a severed ear down a toilet. Though she appears to have a happy marriage to a doting husband, Jackie engages in lunch-hour trysts with Eddie (Paul Schulze), the hospital’s pharmacist. During one of their hook-ups, Jackie purrs, “You had me at annihilation.” It’s a throwaway line, yet it hints at some long-festering, destructive impulse beneath her brisk, high-functioning exterior.

Nurse Jackie shifts awkwardly sometimes from the drama of distressed emergency room patients to moments of broad, zany comedy. As well, Jackie’s colleagues — who include a gay male nurse, an officious hospital administrator (Anna Deavere Smith) and a cocky, young doctor (Peter Facinelli) — are a bit wobbly at the outset. It takes a few episodes before these supporting players rise above clichéd roles that seem lifted from shows like Chicago Hope. Despite its flaws, Nurse Jackie makes for first-rate, highly addictive television, because of the complex, deliciously subversive character at its centre.

Jackie has a touch of Hawkeye Pierce’s lunacy, and when she declares, “I don’t do chatty. Quiet and mean: Those are my people,” she recalls the cranky spirit of Hugh Laurie’s character on House. With her shorn hair and tired, makeup-free face, it’s clear Falco is hell-bent on leaving her last role — as mob wife Carmela Soprano — behind. What she does with Jackie Peyton is far edgier than any of the aforementioned anti-heroes.

Jackie and fellow nurse Mo-mo (Haaz Sleiman, left) confer about a patient in a scene from Nurse Jackie. (Corus Entertainment/Movie Central)

Several of Nurse Jackie’s episodes begin with literary voice-overs (this nurse quotes T.S. Eliot). Jackie’s interior monologues are both smart and comic. She has clearly seen some harrowing stuff, but her attempts at detached humour don’t feel entirely authentic. In a typically deadpan moment, Jackie observes, “Sister Jane de Chantal: what a champ. She’s the one who told me that the people with the greatest capacity for good are the ones with the greatest capacity for evil. Smart f---in’ nun.”

That Jackie knows the difference between good and evil, and yet still commits some morally questionable deeds, makes her a refreshing departure from all of the saintly TV nurses who have preceded her. St. Elsewhere’s Helen Rosenthal ended up addicted to pain pills, but that was only after one of her colleagues died of AIDS. In an effort to make her struggles with alcohol more palatable for viewers, the writers for ER gave Abby Lockhart (Maura Tierney) a turbulent past involving a lousy ex-husband and a bipolar mother.

Jackie, by contrast, arrives without an explanation or an apology, a bitter pill that refuses to go down easily. Perhaps this explains why real-life nurses are complaining about the show. They take issue with Jackie’s drug-taking, but ignore the other instances where Falco communicates, with great empathy, the skills required to perform such a thankless job each day. Jackie knows the shame of having an incompetent doctor dismiss her accurate diagnosis, as well as the absurdity of being asked to work a “double” after being reprimanded for doing 12-hour shifts.

Do those stressful moments account for all the pills she needs to get through the day? Maybe. So far, the only explanation Jackie offers for her sinful behaviour is this: “If I were a saint, which maybe I wanna be, maybe I don’t, I would be like Augustine. He knew there was some good in him, and he knew there was some not-so-good.… Make me good, God. But not yet.”

With each passing week, the writers — Linda Wallem, Liz Brixius and Evan Dunsky — dig a little deeper, revealing cracks in Jackie’s armour that suggest she could be headed for a meltdown similar to the one Didion depicts in Play It As It Lays. Nurse Jackie hasn’t achieved the sustained power of that classic novel, but it does share Didion’s nerve. The show’s heroine touches on something bold, even frightening, that’s seldom depicted on TV. As Jackie surveys her messy life, her face reveals a woman who has no answers. Like Maria Wyeth, she’s forced to conclude: Nothing applies.

Nurse Jackie airs Mondays on the Movie Network and Movie Central.

Lee Ferguson writes about the arts for CBCNews.ca.