Who Are You and What Did You Do to X?

Everything About Fiction You Never Wanted to Know.

A stock phrase to invoke and/or parody "Spot the Imposter" game, that is, happens when someone seems to act out of character. For comedy purpose, usually it's said when the "impostor" performs better.

Occasionally even happens to an actual impostor.

Occasionally, this phrase can be used as a playful compliment, when a character has undergone a makeover, either minor or radical.

Seen It a Million Times.

Examples of Who Are You and What Did You Do to X? include:

Fanfiction

  • Frequently used in Harry Potter fanfics whenever Hermione Granger does anything that defies the Flanderized "homework martinet" characterization she gained in earlier fics.

Film - Live Action

Joy Miller: Who are you and what did you do with the little Nazi kid?

Periodicals

Web Comics

Television

Nate: Who are you and what did you do with Blair Waldorf?

Real Life

  • A common phase related to this trope is "Who died (or left) and put you in change?"