get over on (one)

1. To fool or deceive one. He had a knack for getting over on his parents whenever they suspected him of using drugs. You might be able to get over on your other friends, but not me. I know something's wrong, so tell me what's really going on. Did you honestly think you'd be able to get over on the security guard with a fake mustache?

2. To make one the victim of a prank, hoax, or scam. In this usage, a noun or pronoun is used between "get" and "over," especially the word "one." Trust me, you won't be able to get anything over on Mike. He's as sharp as a tack. The con man spotted Jane from a mile away, and quickly figured out how he would get one over on her. Don't give this guy any money, Mom—he's trying to get over on you!