bang/knock your/their heads together
knock your/their/our heads together
To scold two or more people harshly. If you two do something this stupid again, I'm going to knock your heads together!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
bang/knock your/their ˈheads together(informal) force people to stop arguing and behave in a sensible way: I’d like to bang those stupid politicians’ heads together.
Farlex Partner Idioms Dictionary © Farlex 2017