How do you grow up and make your own life when you're tethered to others? Even harder if the people you're tethered to are both needy and slightly bonkers.

In her debut novel, "The Sisters Sweet," Minneapolis writer Elizabeth Weiss has spun a fascinating coming-of-age novel around this question, even imagining a literal tether. The result is a highly original, engrossing story about family secrets, hypocrisy and betrayal.

Set in the 1920s and '30s in Chicago, the novel is narrated by Harriet, twin to Josie, daughter to Maud and Lenny. Maud once was a Vaudeville performer, with a voice so beautiful "light pours from her throat" when she sings. Lenny was a talented designer of sets and costumes who won Maud's heart by carving exquisite tiny animals out of pilfered bars of soap.

But hard times have hit — diva Maud can no longer perform, and dreamer Lenny has started to drink. They have twin toddlers to care for, and no income. It's Lenny who hits on the clever scheme to truss the girls together, tell the world they're conjoined twins, and put them on the stage.

For 10 years, between the ages of 5 and 15, the girls are a hit, singing and dancing in one big dress with two holes for their heads. Josie is a natural, the one with the talent. Harriet's skill is melting into her sister, becoming one with her. "For the duration of the show, it wasn't a lie; it was simply a different sort of truth. ... I was Josephine and Harriet both."

I won't tell you exactly how Josie rebels — that scene is too audacious to spoil — but afterward the burden of everything falls on Harriet, who at 15 now must be the good girl, the wage-earner, and, eventually, the perfect woman who will marry a fortune and thus provide for her mother's future.

Harriet is a wonderful, full character — wise, observant, torn between duty to her feckless parents and a desire to live her own life. It's not surprising when she tries to maintain a dual existence — isn't that all she has ever known? But it's also not surprising when the center will not hold.

"The Sisters Sweet" has a couple of jarring structural oddities; it's bookended by brief chapters when a reporter ambushes an aged Harriet to find out her story. The device of nosy journalist is a tired one, and, in this case, neither necessary nor believable. ("I called up your publisher and got your address," the bubbly reporter says.)

And Harriet's narration, the bulk of the novel, is interrupted by third-person chapters set deeper in the past. They tell the story of Maud and Lenny, but names are withheld and it takes half of the book for the reader to understand who these people are. While they provide important back story, the chapters are unnecessarily confusing.

But these are quibbles. "The Sisters Sweet" is fiendishly well imagined, a powerful family story about selfishness and duty, sacrifice and freedom. As all around her the people who would use Harriet get what they want in various ways, the reader hopes madly that she will finally figure out a way to undo those ties that bind.

Laurie Hertzel is senior editor for books at the Star Tribune.

The Sisters Sweet

By: Elizabeth Weiss.

Publisher: The Dial Press, 398 pages, $27.