Deal with, assume control of, as in He's going to take their debts in hand and see if they need to declare bankruptcy, or Once the new teacher takes them in hand this class will do much better. [c. 1300] Also see in hand, def. 2.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.