Also, keep one's wits about one. Remain alert or calm, especially in a crisis. For example, After the collision I had my wits about me and got his name and license number, or Being followed was terrifying, but Kate kept her wits about her and got home safely. [Early 1600s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.