What's (someone) playing at?

What's (someone) playing at?

What is someone's agenda? What is someone's ulterior motive? I can't figure out why Janet is suddenly volunteering for the position she said she would never do. What's she playing at? Why are you trying to date my sister? What are you playing at?

See also: play

what’s somebody ˈplaying at?

used to ask in an angry way about what somebody is doing: What do you think you’re playing at?

See also: play, somebody