in league with (someone)

agreeing to do something with someone else.

The accountant and the chairman were in league to hide the company's debts.

I believe my children are in league with the devil!

Usage notes: often said about an activity that is not completely legal or approved of

• designated driver
• de trop
• deus ex machina
• devil finds work for idle hands.
• devil-may-care
• devil take the hindmost
• diamond in the rough
• dibs on
• dibs on something
• dice are loaded against
• dice are loaded against someone
• dice with death
• diddly-squat
• die a death
• die down
• die for
• die-hard
• die hard
• die is cast
• die off
• die out
• die with boots on
• die with your boots on
• difference of opinion
• different ball of wax