Stars Toni Colette, Liev Schreiber, Rebecca Gibney, Anthony LaPaglia; directed by P.J. Hogan; 111 minutes.

Well, it's no Muriel's Wedding. Writer-director P.J. Hogan's new film marks a return to Australia after that impressive 1994 debut and years in Hollywood making films such as My Best Friend's Wedding, but it's nowhere near as effective as that earlier blend of drama and dark and sometimes broad comedy. The Abba songs of the previous film are replaced by numbers from The Sound of Music, on which this movie is in some ways a twisted antipodean variation.

The Moochmores are a family with problems. Father Barry (Anthony LaPaglia) is mayor of Dolphin Heads and is more concerned with his re-election campaign than his five daughters - whose names he can't even keep straight - or his wife Shirley (Rebecca Gibney) who has a breakdown and is sent ''on holiday to Wollongong'' (that is, to a psychiatric hospital). And now each of the daughters is convinced she has some sort of mental problem; one even seems to be genuine.

Enter tough-talking, foul-mouthed Shaz (Toni Colette), literally picked up on the side of the road by Barry, as a nanny for the girls (Hogan says this was based on what actually happened to him and his siblings when his mother was hospitalised and his father couldn't deal with them; maybe so, but it comes off as a hell of a contrivance the way it's handled on screen). And with her self-described mission to be an ''avenging angel of the perpetually humiliated'', Shaz - accompanied by her dog Ripper - helps to make the girls feel better about themselves as they wreak havoc on the sanctimonious types in the neighbourhood.

Whether or not Shaz is justified in proclaiming people like herself and the Moochmores as ''the next stage in human evolution'' is debatable.

And that's not all. One of the daughters, Coral (Lily Sullivan), who works at the aquatic theme park run by shark hunter Trevor Blundell (Liev Schreiber, sporting a very convincing Australian accent), develops a crush on guitar-strumming co-worker Trout (Sam Clark).

These two storylines eventually come together.

While the cast is excellent and performs with gusto, the film tends too much towards loud surfaces and gross-out humour both verbal and visual; there are darker undercurrents at play here but they aren't always as well integrated as they might be. Nor do all the story elements hang together: this is an overlong film that sometimes feels like a series of set pieces, though that effect might be deliberate given the disjointed nature of many of its characters. And the Sound of Music references become a bit much.

Still, if you're attuned to Hogan's particular vision of suburban life and are not easily offended, you might have a slightly warped good time. Just don't expect another Muriel's Wedding.

■ Ron Cerabona is a staff writer