To unexpectedly find someone in an embarrassing or compromising situation.

किसी को अचानक शर्मनाक या समझौतापरक स्थिति में पाना

English Usage: The politician was caught with his trousers down when his scandal was exposed.

Hindi Usage: जब उसकी स्कैंडल का पर्दाफाश हुआ तो राजनेता पकड़ा गया।