An encounter with an angel is supposed to change a person’s life and in quick order. Look what it did for George Bailey in the Christmas classic “It’s a Wonderful Life.”

The trouble is that Grace Hanadarko is no George Bailey and her angel, Earl, bears no resemblance whatsoever to Clarence, who earned his wings and saved the small-town businessman by showing him what life in Bedford Falls would have been like if he’d never lived.

“Saving Grace,” TNT’s newest offering, premieres tonight. Despite a stellar cast, it is a stew made up of elements borrowed from other successful series on cable and network television. It’s a little bit “The Closer” with a big helping of “Rescue Me” thrown in, followed by a dash of “Touched by an Angel” and a pinch of every cop show that has aired in the last decade.

It’s impossible to tell from the first two episodes whether “Saving Grace” will be able to settle into its own niche the way “The Closer,” TNT’s successful Monday offering starring Kyra Sedgwick, has. Whether viewers will tune in week after week to watch an angel, albeit an unconventional one, grapple to save a woman who doesn’t believe in God still is a mystery of the secular kind.

Grace (Holly Hunter) is a hard-living, Southern Comfort-swilling Oklahoma City cop who is having an affair with her married partner, Ham Dewey (Kenneth Johnson). Her angel (Leon Rippy), who already has his wings, chews tobacco and literally tries to wrestle Grace into reforming her life after she, in a drunken stupor, calls for help from the Almighty.

The only person Grace tells about her encounters with her angel is Rhetta Rodriquez (Laura San Giacomo), her best friend since childhood and a forensic scientist. Rhetta believes in God and still goes to church but the scientist in her wants proof that angels and God really exist.

The reason to keep watching “Saving Grace” after the first couple of episodes may not be the angel’s struggle to save Grace from her self-destructive nature, but to see the sparks fly between Hunter and Johnson. Hunter, who won an Oscar for “The Piano,” knows how to play a love story. But her scenes with Johnson, who portrayed Detective Curtis “Lem” Lemansky for five seasons on “The Shield,” are scorching and tender.

Believers, like Rhetta, may stick with the show for the first season to watch Grace wrestle with her angel. Doubters, however, will find the sizzle of Grace and Ham’s “sinning” far more intriguing.