Non-reversible changes result in the formation of new materials. These can be the result of the burning of materials or of chemical reactions. Fire! Fire! observes the Hindu festival of Dessehra, which uses fire to burn the wooden ten-headed King Ravan, producing explosions of fireworks, resulting in irreversible chemical changes. Changed For Ever goes into the lab to observe chemical changes, including time lapse of burning candles and the burning of magnesium. Magic Sand follows the amazing changes in properties which occur between the taking of the raw material sand and the production of finished glass at a glassworks. No Going Back observes two non-reversible chemical reactions in the lab. What's Cooking? goes to Chinatown to see chemical changes in the kitchen: heating, roasting and frying.