Try to take advantage of a confused situation. For example, He often buys up stock in companies declaring bankruptcy; fishing in troubled waters generally pays off. This term, first recorded in 1568, expresses the even older notion that fish bite more readily when seas are rough.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.