Uncovering a mirror in a quarry, Small Clanger becomes horribly obsessive about his discovery. While he proudly shows others his mirror, he refuses to allow anyone else to look at their reflection. Small Clanger's vanity causes him to be selfish and rude to his friends and family.

Nobody wants to speak to him or give him green soup, the Clangers' favourite meal. Soup Dragon makes a deal with Small: he can have some soup if he allows her to look into the mirror. (The Soup Dragon, curious as ever)

Small Clanger does not hold up his part of the bargain, so the Soup Dragon spills her soup over the reflective piece of glass. The mirror eventually falls down, cracking and putting an end to this silly quarrel between friends. Small learns the value of selflessness and friendship.