With no confirmed film or show source attached to this specific clip, You Liar has spread mainly through soundboards and short-form edits as a reusable reaction line. Its popularity comes from how universal the phrase is: almost any argument, prank or storytelling video can set it up with a small contradiction. Creators reuse it because viewers understand the accusation instantly without context, and the short length makes it easy to loop, layer over screenshots and drop into compilations about lying, cheating and getting caught out online.