Choosing to ignore the female penguins, Roy and Silo are inseparable. They sing together, bow to each other and go on little strolls around the penguin enclosure. When they see the other penguins pair up and build a nest of stones they do the same and snuggle up to sleep. Soon however they see that the other penguins all have eggs in their nests. They watch as the eggs grow then hatch, and they want a baby penguin of their own.
Clever Roy spots a large round stone which looks just like an egg. He brings it home to Silo and they pop it in their nest. For days and days they take turns sitting on the egg, just as they have seen the other penguins do, but no baby penguin appears.