There's no room in a good farce for mean-spiritedness, which is what makes the low-key Australian comedy "The Castle" so refreshing.

And it's not as if there aren't chances for the filmmakers to get cruel with the humor. But for the most part, they resist the temptation, and the result is quite charming. In other words, don't be surprised if you end up laughing with the film's eccentric characters rather than at them.

Also, there's a gentleness to the comedy that belies the ultra-low-budget film's R rating (obtained due to a few uses of the so-called R-rated profanity). It also has some of the everyman appeal of the British sleeper hit, "The Full Monty," which certainly doesn't hurt.

Perhaps even more surprising is the level of the film's performances, despite the cast being made up of mostly unknown Aussie TV actors. Of the bunch, the obvious standout is Stephen Curry, who narrates the film as Dale Kerrigan, the youngest son in a family of oddballs.

His father, Darryl (Michael Caton), is a tenacious tow-truck driver. His brother Steve (Anthony Simcoe) is a would-be entrepreneur and bargain-hunter. Another brother, Wayne (Wayne Hope), is an unsuccessful bank robber serving time in prison. And sister Trace (Sophie Lee) is the family success, having obtained a beauty school degree.

Together, the Kerrigans live their version of the Australian family dream, which includes a modest home built on a toxic landfill next to an airport landing strip.

But their way of life is threatened by a proposed airport expansion, and local developers notify the Kerrigans and their neighbors that their property is being "compulsorily acquired" to make way for it.

But Darryl isn't budging. With help from his inept lawyer friend (Tiriel Mora), he plans to save his home by any means necessary.

Needless to say, the film's second half is a comedic test of wills between Darryl and the developers. Fortunately, director Rob Sitch and three other screenwriters never have to force the humor, which feels natural and funnier as a consequence.

Also, the very low-tech filmmaking (it was shot with a Super 16 mm camera) is quite appropriate to the low-key flavor of the story. And a very good cast helps.

In spite of their quirks, the Kerrigans are quite appealing, thanks to the performances — especially those of Caton and Curry, whose clueless but irony-laced narration is a howl.

"The Castle" is rated R for profanity, use of some crude slang and some vulgar references, some athletically related violence and use of a couple of ethnic slurs.