hold for ransom
hold (someone) for ransom
To kidnap someone and keep them until someone else pays a demanded sum of money (a "ransom"). The kidnappers are holding my son for ransom—I'll pay any amount they want!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
hold someone for ransom
to demand money for the return of a person who has been kidnapped. The kidnappers held me for ransom, but no one would pay. We will hold Timmy for ransom and hope that the police don't find us.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.