Come out of the woodwork is a disapproving expression used on someone who suddenly appears in public or does something publicly after ‘hiding’ when seeing an opportunity to get something or to do something unpleasant.
The phrase refers to the idea of vermin, for example, cockroaches crawling out from inside the woodwork of a house.
The earliest written record of the phrase was in the column of New York Day by Day of The Index-Journal, published on December 1, 1930.
The popularity of the phrase raised constantly since its occurrence in 1930 and it got part of the common language in the U.K. as well as the U.S.
The expression appeared in movies such as The Godfather (1972), South park (1997), Adaptation (2002), Zodiac (2007), The Scandal (2012) or King Richard (2021).
Many posts on slang versions of the expression can be found on Urban Dictionary.
The first post was published in 2005.