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Playing Against Type

"You can use the same six people everyone uses. Then, everybody knows what's going to happen. It's always nice in the first 10 minutes when you don't know what the character is going to do."
Albert Brooks when asked by the director why he should play the villain in Drive

The hiring of an actor to play a certain part which differs fundamentally from roles the actor is famous for or has played in the past. For instance, an actress who is known for playing kindly old grandma types suddenly cast as a scheming murderess. This is generally done when an actor wants to 'stretch his/her wings' or 'try something different'. In its highest form, this leads to an Oscar for the actor in question. Often, it can be very useful in The Reveal. Comedies will frequently use this trope for laughs; a wacky line will often sound much funnier coming out of the mouth of someone you'd never expect to say such a thing. If it works very well, it can even turn around a career.

The polar opposite of Type Casting. A source of Hidden Depths. Really bizarre cases (or those which look bad in hindsight) can lead one to ask WTH, Casting Agency?

For specific forms of Playing Against Type, see Tom Hanks Syndrome, Leslie Nielsen Syndrome, Playing with Character Type and New Sound Album.