Steve, Blue & their friends define different occupations.
All of Steve & Blue's friends are pretending to be different occupations, and they play Blue's Clues to figure out what Blue wants to be. They help Steve, who is pretending to be a news reporter and figure out what occupation their various friends are pretending to be. Then they skidoo into a picture of a house building site and help a blue door named Door build his house by calling on the right workers to complete their appropriate tasks.
In the UK Version, Kevin sing the Post Time song with his reporter microphone in his hand.