What is a Preview?
Preview performances are given prior to the opening night of a show.
During the preview period the cast, crew and orchestra are rehearsing during the day and implementing any changes made during the rehearsal process into the performance that evening.
It's a process that allows preparation before we "set" the show for opening night.
After opening there are rarely any changes made to the show.
It's basically our chance to test things out in front of an audience.
For example, there was a number called "Resurrection Man" that was in the original Asolo Production and also in the first few previews here on Broadway. It's a great comedic number but the consensus was that it's 'tone' was different from the rest of the piece. By removing the song we discovered a better flow to the first act.
The opening imagery of the show has also been tightened up in an effort to make the story more clear.
Those are some of the changes that have been made during the preview process.