Final answer:
Metatheatre refers to plays that self-consciously acknowledge themselves as plays, often breaking the 'fourth wall'. It includes elements such as plays within plays and actors playing multiple characters.
Step-by-step explanation:
Plays that refer back to themselves are called 3) metatheatre. The term 'metatheatre' refers to aspects in a play that self-consciously acknowledge the play as a play, as opposed to an attempt to portray 'real life'. This style of theatre breaks the 'fourth wall' - the imagined wall that separates the actors from the audience - and can involve elements such as plays within plays, actors playing more than one character, or explicit references to the fact that the characters are in a play. Shakespeare's 'Hamlet' is a classic example of metatheatre: the play within the play is a key plot element.
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