According to the company, a central piece of George Tsypin's set, a moving platform that holds up to 15 performers, was damaged on May 23. Mechanisms controlling the platform, which used a phalanx of motors to move vertically and horizontally and to pivot, broke because of a computer malfunction. Full technical rehearsals cannot resume until the computer problems are solved and the broken mechanisms are fixed.

"On a technically elaborate new production like Grendel, there are inevitably challenges that need to be surmounted," said Taymor, the director of the production as well as co-writer of the libretto, in a statement. "In commercial theater, there are always preview performances where any problems that arise can be solved. Opera, however, is different, and we expect everything to be worked out by the first performance. L.A. Opera's commitment to this work has resulted in the additional time we need to complete our work."

"This production of Grendel is probably the most ambitious and complex opera ever staged by L.A. Opera," said general director Plšcido Domingo. "Although we in the theater often say 'The show must go on,' until all of the set's technical issues can be resolved, it would be unfair for us to jeopardize the incredible work of Grendel's creative team."

Grendel retells the Beowulf epic from the point of view of the monster. Music is by Goldenthal; the libretto is by Taymor and poet J. D. McClatchy. The cast includes bass Eric Owens as Grendel, mezzo-soprano Denyce Graves as the Dragon, soprano Laura Claycomb as the Queen, tenor Jay Hunter Morris as the warrior Unferth, and tenor Richard Craft as the Blind Harpist. Steven Sloane and Lionel Friend will conduct.

After its run in Los Angeles, the production moves to New York, where it will be seen at the Lincoln Center Festival July 11-16.

Los Angeles Opera is currently contacting patrons holding tickets to the canceled May 27 performance.