The transformation scene is a theatrical convention of metamorphosis, in which a character, group of characters, stage properties or scenery undergo visible change. Transformation scenes were already standard in the European theatrical tradition with the masques of the 17th century. They may rely on both stage machinery and lighting effects for their dramatic impact.
The masques of Inigo Jones and Ben Jonson settled into a form that had an antimasque preceding a courtly display, the two parts being linked by a transformation scene. The scene is an abstract representation of the royal power of bringing harmony.Comus, the masque written by the poet John Milton, implies a transformation scene heralded by the arrival of the character Sabrina.
Change by theatrical means has been seen as central to the pantomime of the Victorian period. After a long evolution, a transformation scene then became standard at the end of Act 1 or beginning of Act 2 of a pantomime. The convention in the middle of the 19th century was of a long transformation scene, of up to 15 minutes.
In the later 18th century, genres including the harlequinade and masque ended with a transformation scene to a temple, drawing to a close with the suggestion of harmony restored.John Rich, earlier in the century, made Harlequin with his slap stick able to transform stage props; and later Joseph Grimaldi as Clown was in charge of transformations. Early pantomime related to and contained the traditional harlequinade by means of a transition in which a group of characters descended from the traditional types from the commedia del arte were transformed and "revealed" as being the key characters in the pantomime of the fairy tale that followed. A production in 1781 of Robinson Crusoe by Richard Brinsley Sheridan is credited with breaking down the rigid separation implied by the transformation, leading to the 19th century view of pantomime.