What is another word for catching the act?
Pronunciation: [kˈat͡ʃɪŋ ðɪ ˈakt] (IPA) 
Catching the act refers to the act of observing someone engaging in an activity that they may not want to be caught doing. Synonyms for this phrase include catching in the act, catching red-handed, and catching someone out. Other synonyms may include detecting, exposing, unveiling, unmasking, discovering, or revealing someone's behavior. Whatever the word used, catching the act implies a sense of surprise, embarrassment, or shame for the person being caught. Whether it is a child sneaking a cookie out of a jar or an employee stealing from the workplace, catching the act suggests that the observer has caught someone doing something they were not supposed to be doing.
