A resident strikes a single match to make morning tea, and an entire corner of a brand-new 22-story skyscraper collapses. The 1968 Ronan Point disaster sounds like a movie plot, but it permanently changed building safety worldwide.

This episode investigates how a tiny spark exposed a massive invisible flaw in global construction, drawing on the official inquiry and modern engineering analysis. It is a story of rapid, unchecked development, a gravity-dependent house of cards design, and the shocking negligence uncovered when the tower was finally torn down.

• The Large Panel System that relied on gravity alone, leaving zero margin for error
• An over-tightened brass nut leaking gas, and the chain reaction of progressive collapse
• How fluid dynamics in the kitchen blast spared resident Ivy Hodge's life
• Demolition ...