Theresa and Robert are not what anyone would consider good parents. They’re grifters, barely getting by through minor schemes. They don’t really have a home, instead squatting in an office next to a bubble factory (the company name is Bubbles, Inc.), where there’s a constant leak of slimy pink foam coming down one of the walls. They keep putting off the landlord, telling him time and again he’ll get the rent soon, but mostly trying to avoid him by ducking down every time they go by his factory. By now, you may have guessed that the title, “Kajillionaire,” does not apply to this couple, even in their wildest dreams.

Their twenty-something daughter, Old Dolio (named after a homeless man her parents knew once), has spent every minute of every day with Theresa and Robert, and thus learned nothing about social interaction. She just goes along with whatever the parents are trying to pull off. For instance, one of their scams involves a post office box they’ve rented so that Old Dolio can reach through every day and grab whatever she can from the adjacent boxes, in the hopes of finding something, anything, of value.

Old Dolio seems like she’s never had a good day in her life. Even when she walks, her arms just hang there, never swinging, as limp as her straight hair, which (like her mother’s) may never have been cut. But she does come up with a new scam they can try, involving air travel and lost baggage, which might net them a hefty check from the airline. On the return flight, the parents sit next to Melanie (Gina Rodriguez), an upbeat woman who loves to talk about her life. When they confide in her, she excitedly goes along with the con, then — caught up in the high of pulling it off — proposes some other ripoffs they can try together.

As the only other human she’s ever had any kind of bond with, Old Dolio is drawn to Melanie in a way she doesn’t understand. She’s also exposed to a new experience when she agrees to attend a parenting class for a stranger who’ll pay her a few dollars. There, Old Dolio learns that there are people in the world who really want to bond with their children and don’t just think of them as members of a crew. It’s as if a door has cracked open a bit and some sunlight is finally finding its way into her life.

I have long been a fan of con artist movies, but “Kajillionaire” is different, in that the scammers are so pitiful and not very likable. Their world, as laid out by writer/director Miranda July, is seedy and desperate. The same words could have been applied to Mose and Addie in Peter Bogdanovich’s 1973 classic “Paper Moon,” but he balanced their precarious circumstances with regular bouts of humor (thanks to the legendary Madeline Kahn), a trait “Kajillionaire” doesn’t share.

Fortunately, Robert and Theresa are played by two veteran actors who never fail to give great performances — Richard Jenkins and a nearly-unrecognizable Debra Winger — who infuse them with a weird sense of humanity amid some obvious mental health issues. However, the one I was really pulling for was Old Dolio, a wary and weary soul played by Evan Rachel Wood with a shy strength and a yearning for a fuller existence.

“Kajillionaire” made for an interesting study of characters with rarely-told stories — even if I’d never want to spend any time with them in real life.

I give it a 7 out of 10.