1) Marie and Johnny, two school friends who have feelings for each other, sneak away to the science lab after school. However, Marie worries her boyfriend Alfie will find out. 2) The next morning, newspaper headlines report two school children were killed in a suspicious fire at the school. 3) A flashback reveals Alfie saw Marie laughing with Johnny on the phone and became jealous and angry, motivating him to seek revenge through the fire.