Warner was due to kick off the venue's 2013-2014 season this autumn (13) by taking charge of Tchaikovsky's Eugene Onegin, a co-production with officials from the English National Opera, but she has been forced to pull out of the engagement due to "an unexpected surgical procedure and the expected recovery time".
The director has recruited her close friend and frequent collaborator Shaw to take her place - and the show will go on as planned on 23 September (13).
Peter Gelb, the Met Opera's general manager, tells the Wall Street Journal, "To lose (Warner) for the opening production is no small thing. But the solution that she and Fiona have come up with is a remarkably creative idea. They know each other inside out."
Shaw, who played boy wizard Potter's cruel aunt Petunia Dursley in the film franchise, admits the task is a daunting one but she is looking forward to the challenge.
She says, "It's a big thing to take on someone's mental imaginative world. It's an unusual thing, definitely, but I think it's the right thing."
The 55 year old is no stranger to theatre acting and directing - earlier this year (13), she staged a one-woman show with Warner, The Testament of Mary, on Broadway, while she has previously directed Vaughan Williams' Riders to the Sea and Mozart's The Marriage of Figaro for the English National Opera.
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