understudy

An understudy is a performer who regularly prepares to take over a principal role in a live production if the regular actor is unable to perform. The role is to ensure the show can continue smoothly in the event of illness, injury, or other absence. Understudies are typically required to be ready to go on with little notice and must know the character’s lines, blocking, and cues.

The theatre world distinguishes several related roles. An understudy usually covers one or more specific principal parts and may perform in the show when not activated. A standby is a closely prepared performer who is ready to go on at short notice and may not appear in performances every night. A swing covers ensemble parts or multiple principals, often without a fixed single character to anchor their schedule. In musicals, the terms cover and standby are common, while in some theatres the same person may be described as a cover for a lead role or as a swing for multiple parts.

Understudies typically train alongside the main cast, attending rehearsals to learn lines, blocking, musical cues, and character development. They may participate in off-stage or off-book rehearsals and must maintain readiness, sometimes stepping into performances with minimal rehearsal time. Their duties include monitoring performances for changes and staying prepared to perform at a moment’s notice.

In practice, understudies provide a vital safety net for productions, helping preserve schedules and audience experience when principal actors are unavailable. The specific terms, duties, and compensation for understudies vary by production, venue, and contractual agreements.