Agent Z and the Penguin from Mars.

Agent Z And The Penguin From Mars was a 1996 Children's BBC sitcom, based on the book of the same name by Mark Haddon. The six episode series followed the exploits of Ben Simpson, played by Duncan Barton, and his friends Barney, played by Andrew McKay, and Jenks, played by Reggie Yates, who together formed the "Crane Grove Gang", named after the street where they lived. This was a society dedicated to playing ingenious practical jokes in an initiative called "Agent Z".