Rumours are spreading around the zoo that a mystery animal is due to arrive. But who could it be? All the animals are in on the game of 'Guess Zoo' and as more and more clues are unearthed Geoffrey begins to suspect that the new arrival is a silverback to replace Jurgen. While the zoo animals continue to speculate, the keepers are busy building the new home for whoever is moving in. As the new animal arrives at the zoo gates, tensions rise. Will keepers Matt and Craig have finished the new animal's home? And will Geoffrey be proved right, are Jurgen's days numbered