Amy Adams and Emily Blunt are entrepreneurs in Sunshine Cleaning.

Overture Films / Lacey Terrell

The story of a pair of down-and-out sisters who try to improve their lot by establishing a company that cleans up the bloody messes left behind by the violently departed sounds like it might at best be either a one-joke idea or, well, icky.

But Megan Holley’s script for Sunshine Cleaning brims with wonderful surprises, daffy situations and goofy one-liners. It goes way beyond its bare-bones premise to delve into the mixed-up, messed-up lives of Rose and Nora — one of them irresponsible in love, the other just plain irresponsible — and leaves one with a sense of growth and touching sensitivity. In Amy Adams’ Rose and Emily Blunt’s Norah she has found a pair of unlikely characters who win affection and sympathy, even as they screw up their lives and the lives of those they love. And she has surrounded them with characters who are as clueless as they.

Rose is a single mother in New Mexico who is unlucky at love, yet has the power of positive thinking on her side, even when things go awry. She tries to convince herself that she is at the center of her universe by reading aloud the Post-It notes she has stuck to the bathroom mirror — “You are strong. You are powerful. You can do anything. You are a winner.”

She’s a hotel maid, but wants something better, something that will help her put her problematic 7-year-old son, Oscar (Jason Spevack), into a private school. Oscar’s latest fetish is licking everything in sight, from the school wall to his teacher’s leg, and Rose thinks a new school might better suit him. Rose is in the middle of a hot adulterous affair with Oscar’s father, Mac (Steve Zahn), a police detective who wants to have a wife and an uncomplaining mistress on the side. Mac encourages Rose to go into the business of cleaning up crime scenes to better her lot. To Rose that seems to be just the ticket to a new life since she already has experience cleaning up as a hotel maid.

But she needs a partner. Her father (Alan Arkin) is a dreamer, a sucker for trying get-rich-quick schemes like marketing strawberry-flavored popcorn to candy stores or peddling not-so-fresh shrimp to restaurants whose owners turn up their noses at the smell.

Rose’s younger sister, Norah (Blunt), whom Rose has looked after like a mother hen since their mother died when they were little, is a waif with blue highlights in her hair and tattoos on a forearm. Nora seems to be unsuccessful at anything she tries, the latest disaster being waitressing. But Rose, undeterred by the reality of Norah’s situation, convinces her to join her “post mortem specialized cleanup operation,” which Rose has brightly named Sunshine Cleaning.

Cleaning up after dead people is not as easy as it sounds. It’s not a pretty job. There’s often a lot of blood and other detritus, plus the job of getting rid of the stench left behind. It requires special training and a license for depositing biohazardous waste. You can’t just toss bloody clothes into a garbage can. But director Christine Jeffs manages to find a certain amount of humor in all this — check out the scene in which the girls are trying to carry a blood-soaked mattress to a dumpster and Norah trips and falls onto it.

There’s also a lot of heart here and scenes that win sympathy for Rose and Norah, who usually tries to do the right thing even as she’s inevitably doomed to fail. Rose, too, is often blindsided by her belief in herself. At one point she runs into an old high school classmate who invites her to a baby shower where Rose babbles on and on about her new business, proud that she has become a successful businesswoman, but totally oblivious to the fact that she’s making her listeners recoil in disgust at her tales of mopping up blood.

In matters of romance, she’s too often second-hand Rose. As she puts it, men always flock around her, but not one of them ever stays very long or asks her to marry him. She doesn’t understand her son’s problems. Her attempts to mother Norah are met with resentment. Rose may be savvy at business, but we see how fragile she is in her personal life.

Holley has included a great deal of background material on Rose and Norah so we can understand their foibles and how they got to this point in their lives, and the actresses make them very real women who are trying to overcome their monumental problems.

Besides Arkin’s endearing huckster of a father and Oscar’s endearing oddities, Holley has added a string of offbeat characters and situations that enrich the story. They include Winston (Clifton Collins Jr.), the one-armed ponytailed owner of a cleaning supply company who takes a shine to Rose. And there’s Norah’s surprising tenderheartedness which peeks out from behind her façade of toughness when she finds pictures of a little girl in the home of a woman whose decaying corpse was discovered alone and sets out to find the woman’s grown-up daughter today. Unfortunately this leads, as most of Norah’s endeavors do, to an unhappy end.

But not so for Sunshine Cleaning which goes way beyond being a “chick flick” to something that has a lot to say about life, the stumbles we make and the persistent attempts to triumph over adversity.

*****Sunshine Cleaning

Starring: Amy Adams, Emily Blunt, Steve Zahn, Alan Arkin, Jason Spevack, Clifton Collins Jr.

Rated: R, contains adult themes, profanity, violence, sexual situations.

mjanuson@projo.com