the brains behind something

the brains behind (something)

The person responsible for a certain plan or idea. Sheila is the brains behind our new environmental initiative, so she deserves all the credit. I wonder which of my enemies is the brains behind this latest rumor about me.
See also: behind, brain

the ˈbrains behind something

the person who thinks of new ideas and makes plans for somebody/something: Everyone knew that she was the real brains behind the operation.
See also: behind, brain, something