have all the aces

To be in a position of power or control over someone or something else. Likened to having the best hand in a card game. He's bigger than me, and stronger, and faster—he just has all the aces. Now that Charlotte knows about us, she has all the aces—I imagine it won't be long until she tells my wife what she saw. A: "I thought you weren't going to confront Margaret." B: "Well, now that I have security footage of her stealing, I have all the aces. I can do whatever I want—like call the cops right now."

have/hold (all) the ˈaces

(also hold all the ˈcards) be in a controlling position because you have certain advantages over another person: The Labour Party candidate holds all the aces — he’s local and well liked.