When Small and Tiny Clanger discover the Froglets — little orange aliens who live nearby — shivering from the cold, they decide to help. To warm them up, they fetch their favourite dish, blue string pudding. But the Froglets have ideas of their own. Instead of eating it, they wrap themselves up in blue string like scarves and feel much warmer.

The Soup Dragon, curious as ever, pops up to see what's going on and mistakes the Froglets' new 'clothes' for food. With the soup running short and their friends in trouble, Tiny and Small cut up Mother Clanger's best tablecloth to make proper shawls for the chilly Froglets.

Mother Clanger is horrified to find holes in her beautiful tablecloth, but before she can scold anyone, something extraordinary happens. A visitor from space lands on the Clangers' quiet little planet. The astronaut plants a flag and a curious machine, then blasts away again, leaving the Clangers with an unexpected gift — a bright new flag that makes the perfect replacement tablecloth for Mother Clanger.