The Welsh-born singer Shirley Bassey enjoyed the distinction of inaugurating the Marquis - in the Marriott Marquis Hotel at Broadway and 46th Street - the first new musical theater to be built on Broadway in 13 years.
A relentlessly aggressive belter, whose mixture of hard-edged glamour and proud, unbridled egotism exemplifies the Las Vegas-Atlantic City pop ethos, Ms. Bassey filled the house with her large, metallic alto.
She is a glitzy camp diva, who affects the same bogus British upper-class regality that many Americans mistake for aristocracy. Ms. Bassey sings songs the way Joan Rivers dishes the dirt, pouncing on a lyric, seizing it with her teeth and shredding it to bits.
At Wednesday's opening-night show of an engagement that ends Sunday, the singer made George Harrison's gentle lyric for ''Something'' (''Something in the way he moves, attracts me like no other lover'') sound like the reflections of a barracuda zeroing in on a goldfish. The song became a threat.
When Ms. Bassey is in full command of her resources, as in her last Carnegie Hall appearance where she had the advantage of a 40-piece orchestra with strings, she exudes an undeniably feisty grandeur. But in her Marquis engagement, the singer has only a small, brass-heavy ensemble as accompaniment, and it accentuated her vocal harshness. On Wednesday, both her voice and the instrumentation were miked to nearly earsplitting levels. Technically, Ms. Bassey was also far from her peak. Many notes rang not only abrasively but flat. The songs that tended to fare the best were self-congratulatory warhorses: ''New York, New York,'' ''My Way'' and especially ''I Am What I Am.''
George Kirby, who opened for Ms. Bassey, delivered skillful comic impressions of performers as diverse as Michael Jackson, Louis Armstrong, Sarah Vaughan, Maurice Chevalier and Hermione Gingold.