MLB (S5 E21)

Sabrina: *smiles confidently as she sighs in relief* There was no proof! *Lila is taken aback.* Well, until now! *Sabrina brings out a button remote and presses it, revealing that the temporary restroom was a trap set for Lila and Chloé, showing everyone their true motive. The mirror now shows the other side of the wall, where the whole class and faculty are seen to be standing just right outside the temporary restroom* Marinette:You've just told everyone who you really are, Lila.