catch someone with their pants down
US /kætʃ ˈsʌm.wʌn wɪð ðer pænts daʊn/
UK /kætʃ ˈsʌm.wʌn wɪð ðer pænts daʊn/
1.
to discover someone doing something wrong or embarrassing, or to find them unprepared for something
:
•
The boss caught him with his pants down when he was playing games on his computer during work hours.
•
The sudden inspection caught many employees with their pants down, as they hadn't prepared their reports.