Place this clip at the exact frame the unbelievable claim lands, then follow it with a bruh for the letdown or an oh my god meme beat if the reveal keeps escalating in your edit.
About this sound
A short French voice clip of someone blurting out 'Mais nan !' — 'but no way!' — in one sharp, incredulous burst. It lands as pure disbelief mixed with amusement, the kind of stunned reaction you get when something absurd is said completely seriously and you cannot quite believe you heard it.