Tonight is an evening of imports.

First up is “Kath and Kim,” inspired by an Australian sitcom of the same name, debuting at 8:30 p.m. on NBC.

Well-paired with “My Name is Earl” at 8 p.m., “Kath and Kim” is another entertaining, white-trash buddy comedy.

Kath Day (played by “SNL” alum Molly Shannon) is a fortysomething single mom who has finally found love, in the form of sandwich-shop owner Phil Knight (John Michael Higgins).

But just as things are starting to go right for Kath, her self-absorbed daughter Kim (Selma Blair) leaves her husband of six weeks and moves back in with her mother. So Kath must try to keep her relationship with Phil afloat despite the interference of her daughter.

Kath and Kim are the types of people who keep our narcissistic, celebrity-driven society alive. When they’re not sniping at each other, they’re bonding over Britney’s latest mishaps or shopping at the mall (or both).

While “Kath and Kim” is definitely the weak link of NBC’s stellar Thursday comedy lineup, it’s also the best of a thin crop of new sitcoms. The two leads have a strong chemistry together, and it’s easy to buy them as mother and daughter.

Two new shows, both coming from England with science-fiction bents, premiere at 10 p.m.

On CBS is “Eleventh Hour,” executive-produced by, among others, TV hitmeister Jerry Bruckheimer.

“Eleventh Hour” is the story of Dr. Jacob Hood (played by Rufus Sewell), a genius biophysicist and special science adviser to the FBI. Hood’s mission is to track those who would abuse scientific discoveries. His bodyguard is Special Agent Rachel Young (Marley Shelton), who stoically puts up with her wayward charge.

This version of “Eleventh Hour” has two strikes against it. First, anyone curious about this show after the May upfronts could order the British original from their favorite DVD-rental service. They got a much more robust series, with Patrick Stewart (the revered Capt. Picard) as Hood and Ashley Jensen (“Ugly Betty”), Scottish brogue and all, as Rachel. This comparison becomes particularly evident in the premiere, lifted almost word for word from its British counterpart.

Second, it’s debuting at the same time as Fox’s “Fringe,” which also probes scientific anomalies, only with more characters, color and conspiracies mixed in. “Eleventh Hour,” sadly, won’t win this challenge.

So, despite having a top lead-in in “CSI,” the clock soon may strike 12 for “Eleventh Hour.”

The other new option in the time slot is “Life on Mars.”

The series centers on New York City detective Sam Tyler (played by TV veteran Jason O’Mara). Tyler’s cop girlfriend Maya is abducted by a serial murderer whom the police mistakenly had let go.

While hunting for Maya, Sam is struck down by a car. When he wakes up, he finds himself in 1973, dressed in a leisure suit with his Charger nearby.

Sam is the new transfer to the 125th Precinct, and he doesn’t win over his new squad mates, played by Harvey Keitel and Michael Imperioli (“The Sopranos”), with his story of coming back from 2008.

Sam must learn to do his job without such common police tools as forensics and computers and tolerate such unwritten tactics as beating suspects and discriminating against female cops. But he does earn the grudging respect of his co-workers despite his wacky ideas.

Underlying the action and the period trappings are several questions: Did Sam actually travel through time? Is he a lunatic? Is he in a coma, imagining what’s happening around him?

O’Mara deserves a hit, and with a strong cast around him, he has a chance against unproven “Eleventh Hour” and “ER” in its last season. “Life on Mars” may have continued life at 10 p.m.