A suspicious character, thinking a friend or loved one is lying, goes along with the lie, forcing the liar to expand upon the cover story in a grossly outlandish fashion. Named for "pull the thread, and watch the sweater unravel." In a comedy series, this can result in a Fawlty Towers Plot situation. In a drama, it results in the catastrophic collapse of a villain's house-of-cards scheme. May result from Spotting the Thread. Not to be confused with All Cloth Unravels, when literally pulling a single loose thread on a piece of clothing causes the whole piece of clothing to come undone.