An episode in which the main character is rendered tragically/comically invisible and wackiness commences to ensue. This can be done to give the lead actor a small break so they can skip principal photography. It also allows an opportunity to give that character unexpected insights into his or her own character via the overheard statements of others, or to do things they wouldn't normally do. See Invisibility for when this is a character power or otherwise longer than a one-shot storyline. See also: Near-Death Clairvoyance, I Can't See Myself, Invisible Streaker, Invisible Jerkass.