The characters in “Heartbreakers,” like the movie itself, are broadly farcical for a while, then supposedly sympathetic, then somewhere in the middle. Actually, they’re always somewhere in the middle as far as viewers are concerned, because they’re never quite likable, but neither are they ever all-out wacky.

It’s yet another film that tries to have its cake and eat it, too, squandering a talented cast and screwing up a perfectly good premise in its attempts to be both loony and emotional.

Max (Sigourney Weaver) is a gorgeous con artist whose outfits are so nice and numerous that Ms. Weaver’s costume designer gets a special mention in the opening credits. Max’s scam is to find wealthy men and marry them as quickly as possible. Then, shortly after the wedding, her daughter Page (Jennifer Love Hewitt) — having gotten a job as the guy’s secretary or maid in preparation for the event — seduces the guy, Max catches them, and there’s a healthy divorce settlement.

The film begins with the latest victim, stolen-car dealer Dean Cumanno (Ray Liotta, apparently still missing some of his brain after “Hannibal”). He and the other targets, of course, never know that Max and Page (who work under aliases) have any connection to each other, and mother and daughter are free to move somewhere else with the loot and try another scheme.

Page wants to set out on her own, but Max doesn’t think she’s ready for it. After Dean gets screwed, they’re forced to do one last gig together because the IRS has caught up to them and they owe hundred of thousands of dollars in interest and penalties.

They want to make it a doozy, so they head to Palm Beach, home of rich men who aren’t too swift (see the Florida presidential election for evidence of that). Max adopts a Russian accent and cozies up to tobacco billionaire William Tensy (a smoker’s-hacking Gene Hackman). She conspires to get rid of his suspicious maid (Nora Dunn), which is a double blessing, because it opens up a household position for Page, thus setting the scene for the wedding and subsequent divorce-by-entrapment.

While waiting for mom to win Tensy’s love, Page hits it off with a local bartender (Jason Lee) who himself may be worth some money. Max keeps warning her about actually falling in love with a victim: That’s what happened to her, back in the day, and it resulted in an unwanted pregnancy who turned out to be named Page.

As mentioned, it’s the film’s uneven tone that does it in. Max and Tensy tend to stay goofy, what with her fake Russian accent (in one scene, she encounters a waiter who actually speaks Russian — with predictable results). Page and Jack the bartender, meanwhile, are the more romantic couple, with Page’s duplicity causing her much conflict.

This arrangement is fine, especially since Sigourney Weaver and Gene Hackman can both pull off comedy when they want to, and Jennifer Love Hewitt is more suited to doe-eyed pining.

It’s when the two tones mix that things get ugly. Max suddenly has to think of what’s best for her daughter and whether she’s ruining her life by keeping her involved in fraud, and Page has to help Max dispose of a body after an ill-timed death by natural causes. Oh, and Dean shows up again. It’s all too wacky and serious and romantic and stupid, all at once.

Weaver and Hackman, as mentioned, do fine work. Jason Lee’s wimpy-wisecracky delivery serves him well, and he acts circles around the moony Ms. Love Hewitt, who is clearly outranked by everyone in the cast.

(There’s also the matter of how the film presents men: as shallow creatures who can easily be persuaded to do anything if you promise them sex. This is a fine stereotype, as far as stereotypes go — but so is the one that women only like to gab on the phone and go shopping, and whenever a movie presents women that way, everyone decries it as “sexist.”)

There are scattered laughs amidst the predictable predicaments, but they’re scattered over the film’s two-hour running time (which is about 30 minutes too much). I didn’t know whether to laugh or cry. So I did neither.

C (; PG-13, frequent profanity, some strong sexuality.)