In theater, a dress rehearsal is the final rehearsal a performing company
stages before opening night. This rehearsal is intended to be as close to the
true performance as possible. The term dress rehearsal stems from the fact that all of
the performers are in full costume and makeup for this rehearsal. Additionally,
all of the sets and props are ready and in use, the stage lights are used as they
would be during the performances, and any special effects are included.
A dress rehearsal is supposed to proceed exactly as the performance will - the director
will not stop the action, the scene changes will be performed as intended, and actors
are generally expected to approach the rehearsal in the same way they would a full performance.
Depending on the director and producer, a small audience may be invited to the dress
rehearsal. If an audience is invited, it may consist of family and friends of the cast and crew,
or may be another group arranged by the producer. Critics and other VIPs are generally not
invited to a dress rehearsal, as it is often riddled with errors.
Incidentally, most thespians consider a problematic dress rehearsal as a good omen for the
performances. Some people who scoff at this superstition say that it's all in the psychology of
the performers, that they get all the jitters worked out, and recognize that they can make it
through the performance even when mistakes or other weird events happen. Due to another superstition,
the dress rehearsal may be the only version of the performance a director sees, as many directors
consider it bad luck to attend the performances. | 
