come out of the woodwork

From the idea of insects crawling out from inside the woodwork in a house.

• "He won the lottery last year and he has had old "friends" and distant relatives coming out of the woodwork ever since."
• "[...] 90-day wonders [...] were kicked around by harassed Regulars who were [...] just too busy to take time to spare the feelings of those strange creatures who came out of the woodwork and wanted the privileges of officers, without being fully prepared to do the work of officers."
• "Would-be informants came crawling out of the woodwork, drawn to McCarthy as moths to light, each peddling a new version of Lattimore's evil deeds."
• "And suddenly they came out of the woodwork. I don't actually know what that expression means. What come out of the woodwork? Cockroaches maybe. Mice?"
• "With the fall of the fascist regime, Italy was virtually overrun by several political parties who came out of the woodwork to fill in the vacuum."

• crawl out of the woodwork
• bring out of the woodwork
• pull out of the woodwork

• blend into the woodwork

• come out of the closet
• coming out of one's ears
• out of nowhere
• out of the blue