A switcheroo is a sudden unexpected variation or reversal often associated with a joke (sometimes "the old switcheroo"). It is often used colloquially to refer to an act of intentionally or unintentionally swapping two objects.

As a comedic device

Comedic device

A comedic device is used in comedy to write humor in a common structure. They can become so common that they are difficult for writers to use without being perceived as cheesy.-Double entendre:...

, this was a favorite of Woody Allen

Woody Allen

Woody Allen is an American screenwriter, director, actor, comedian, jazz musician, author, and playwright. Allen's films draw heavily on literature, sexuality, philosophy, psychology, Jewish identity, and the history of cinema...

; for a time, he used so many switcheroos that friends referred to him as "Allen Woody." Some of Allen's switcheroo gags were:

• Carrying a sword on the street, in case of an attack it turned into a cane, so people would feel sorry for him
• Carrying a bullet in his breast pocket; he claimed someone once threw a Bible at him and the bullet saved his life.

Another example comes from the film The Aristocrats

The Aristocrats (film)

The Aristocrats is a 2005 documentary film about the famous dirty joke of the same name. It was conceived and produced by comedians Penn Jillette and Paul Provenza, edited by Emery Emery, and released to theaters by TH!NKFilm...

, wherein Wendy Liebman

Wendy Liebman

Wendy Liebman is an American stand-up comedian known for her distinctive style which includes quick, clever follow-ups after her jokes. She starts the joke leading it to one direction then changes it. As in "This Thanksgiving I made a 28 pound turkey .....

 pulls "the old switcheroo". Whereas the joke normally is narrated as a vulgar series of actions followed by the clean punch line, Liebman narrates a very aristocratic series of actions followed by a very vulgar punch line.

In his book, Gödel, Escher, Bach

Gödel, Escher, Bach

Gödel, Escher, Bach: An Eternal Golden Braid is a book by Douglas Hofstadter, described by his publishing company as "a metaphorical fugue on minds and machines in the spirit of Lewis Carroll"....

, Douglas Hofstadter names one of the rules in his version of Propositional calculus

Propositional calculus

In mathematical logic, a propositional calculus or logic is a formal system in which formulas of a formal language may be interpreted as representing propositions. A system of inference rules and axioms allows certain formulas to be derived, called theorems; which may be interpreted as true...

 the Switcheroo Rule, apparently in honour of an Albanian railroad engineer, name Q.q.Switcheroo, who "worked in logic on the siding". This is in reality the disjunctive syllogism

Disjunctive syllogism

A disjunctive syllogism, also known as disjunction-elimination and or-elimination , and historically known as modus tollendo ponens,, is a classically valid, simple argument form:where \vdash represents the logical assertion....

.

See also

• Comic strip switcheroo
  Comic strip switcheroo
  The Comic strip switcheroo was a series of jokes played out between comic strip writers and artists, without the foreknowledge of their editors, on April Fool's Day 1997...
  
  
• Variation on a theme
• Bait and switch
  Bait and switch
  Bait-and-switch is a form of fraud, most commonly used in retail sales but also applicable to other contexts. First, customers are "baited" by advertising for a product or service at a low price; second, the customers discover that the advertised good is not available and are "switched" to a...
  
  
• Man bites dog trope
• The Great Switcheroo
  The Great Switcheroo
  "The Great Switcheroo" is a short story by Roald Dahl published in Playboy magazine. It was included in the collection Switch Bitch published in 1974 by Michael Joseph Ltd.-Plot summary:...
  
  
• In Soviet Russia
• Transpositional pun
  Transpositional pun
  A transpositional pun is a complicated pun format with two aspects. It involves transposing the words in a well-known phrase or saying to get a daffynition-like clever redefinition of a well-known word unrelated to the original phrase...