You can't accuse producers of the new Broadway musical "Next to Normal" of timidity. The show, which deals with a suburban housewife's descent into mental illness and its traumatic effect on her family, is not exactly surefire commercial fare, despite the generally positive reception it received in earlier productions.

It would be nice to report that the musical is an artistic triumph, but it remains a decidedly mixed bag despite many laudable aspects. It has been retooled extensively since its off-Broadway premiere at the Second Stage -- mostly for the better -- but still doesn't live up to its artistic ambitions.

Brian Yorkey's book and lyrics track the disintegrating mental state of Diana (Alice Ripley), traumatized years earlier by an event that -- in the interest of maintaining the surprise of one of the show's more strained plot twists -- will not be revealed here.

Her loving husband Dan (J. Robert Spencer) is at a loss to deal with her condition, which has failed to be controlled by an endless series of doctors and medications, and teenage daughter Natalie (Jennifer Damiano) is dealing with identity issues of her own and a burgeoning romantic relationship with a pot-smoking fellow student (Adam Chanler-Berat). Only teenage son Gabe (Aaron Tveit) seems unfazed by the chaos.

Eventually, Diana finds herself in the hands of a "rock star" therapist (Louis Hobson) who subjects her to shock-therapy treatments with an unfortunate side effect of memory loss.

The pop-rock musical score by Tom Kitt ("High Fidelity") boasts catchy numbers, notably Gabe's passionate declaration "I'm Alive" and Diana's witty ode "My Psychopharmacologist and I." But the music, delivered by a six-piece band, proves repetitive, lacking the stylistic variety the complex subject matter demands.

While admirably attempting to examine an undeniably important and too-little-discussed health issue, "Normal" is too superficial to be taken seriously, and its explanation of the cause of Diana's illness feels entirely too pat. (This might be a minority opinion, judging by the reactions of many clearly moved audience members.)

Director Michael Greif gives his staging the full "Rent" treatment, infusing the proceedings with perhaps more energy than advisable. And Mark Wendland's abstract, three-tiered set is more redolent of a futuristic cell block than a suburban house.

There should be no quibbles, though, about Ripley's powerfully fierce and moving performance, which should garner significant attention come awards time.

Venue: Booth Theatre, New York (Runs indefinitely)
Cast: Alice Ripley, J. Robert Spencer, Aaron Tveit, Jennifer Damiano, Adam Chanler-Berat, Louis Hobson
Music: Tom Kitt
Book/lyrics: Brian Yorkey
Director: Michael Greif
Musical staging: Sergio Trujillo
Set designer: Mark Wendland
Costume designer: Jeff Mahshie
Lighting designer: Kevin Adams
Sound designer: Brian Ronan