Also, blow wide open. Expose, especially a scandal or illegal activity. For example, The newspaper's investigation blew the lid off the governor's awarding state contracts to his friends. [First half of 1900s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.