When it was announced that Ann Reinking was stepping into the role of Roxie Hart in the Boston Shubert Theatre leg of the national tour April 22- May 16, it was not to be interpreted that she would actually begin performances April 22, according to the show's spokespeople.

Belle Calaway went on as Roxie April 22 in Beantown and continues to April 25 while Reinking gears up to begin shows there April 27. Originally to close in Boston May 16, Chicago has been extended to May 30.

There is no casting confirmation for the extension.

Reinking's return to the role she created in the 1996 Broadway revival is as the star fill-in for an injured Sandy Duncan, who broke her foot while in rehearsals with the national tour in Sacramento the week of April 12.

Duncan is still expected to take over the Roxie role on Broadway May 25. Her doctor expects her foot to be healed by that time, according to a spokesman. Co-starring in Chicago at Boston's Shubert are Ruthie Henshall as Velma, Adrian Zmed as Billy, Carol Woods as Mama Morton and Bruce Winant as Amos.

Henshall starred as Roxie in the London staging of the revival, but switched roles when she crossed the ocean. Henshall moves to the Broadway production May 25.

Reinking, busy with staging Fosse over the past year, hasn't recently stepped into the shoes of Roxie. She won a 1997 Tony Award for choreographing -- "in the style of" Bob Fosse -- the 1996 revival of 1975 Chicago, by John Kander, Fred Ebb and Fosse.

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In the meantime, Ute Lemper has finished her return run in the Broadway company of Chicago and Nancy Hess, one of the most-employed actresses in American musical theater, now plays Velma Kelly.

Hess was standby for both Velma and Roxie in New York, and has a solid reputation on Broadway appearing for Chita Rivera in The Kiss of the Spider Woman, for Bernadette Peters in The Goodbye Girl and for roles in Me and My Girl, Jerome Robbins' Broadway and On Your Toes.

For Boston information, call (800) 447-7400.