get wise to (someone or something)
To become fully aware or cognizant of someone or something, especially if he, she, or it is suspicious, illegal, or malicious in nature or intention. We'd better watch our step—I think the police are getting wise to us! I hope my brother doesn't get wise to my scheme to take over the company.
get wise to
Also be wise to. See through the deception of; also, become aware of. For example, It took a while, but she finally got wise to Fred's lies, or I'm wise to the fact that her clothes come from a thrift shop. [Colloquial; mid-1800s]
be/get ˈwise to somebody/something
(informal) be/become aware of something or aware of somebody’s (usually bad) behaviour: When did you first get wise to what was happening?He thought he could fool me but I’m wise to him.