keep an act up

To maintain a façade or false set of behaviors in order to deceive people. Other words can be used between "keep" and "act." The company has kept the act up for so long that I think even they believe their own story at this point. I'm tired of keeping this act up. I just want to tell the world the truth about our relationship! Audiences are left at the end of each episode wondering how much longer the villain can keep her act up before her true colors emerge.

to maintain behavior that is a false show; to continue with one's facade. (The an can be replaced with the, this, that, etc.) How long do I have to keep this act up? I am tired of fooling people. I am weary of keeping up my act.