Diamanda Galas' most famous work is "Plague Mass." Her music has been called "schrei opera"--from the German word for "shriek." With a wildly shifting three-octave range and songs about tragic love, AIDS and the kind of joy that only arises from deep despair, Galas doesn't entertain, she threatens.

At the Wiltern Theatre on Friday, it was a surprise that the gothic diva's show,"Malediction and Prayer" Concert for the Damned," was a short a no-nonsense affair that lasted little more than an hour. Alone with her piano, Galas only addressed the audience-a colorful colection of gothic neo-primitives, drag queens and other art lovers-to dedicate a song to Clive Barker.

There were no operatic digressions; no real pyrotechnics. But Galas is a terrific interpreter of old blues standards and, happily, this set harked back to her blues-based 1992 album, "The Singer." She may dress like Morticia Addams, but she has the heart of a Robert Johnson.

Galas dleivered a spellbinding take on Johnny Cash's"25 Minutes fo Go"--a "Dead Man Walking" in song--capturing Cash's condemned person's last minutes while punctuating her own work dealing with AIDS. The highlight of the too-short show was a harrowing cover of Willie Dixon's "Insane Asylum." As she alternated between telling a tale about finding one's love insane, and delving into the musical equivalent of speaking in tongues, Galas proved that she dares to go to the hellish depths of her stories.

A channeler of spirits that range from the exquisite to the downright gruesome, Diamanda Galas is anything but subtle. After this show, you wanted to thank her for it.