Biffy Ferguson is a large, eight year old Tabby Cat with an odd orange tip on the end of his tale that he is rather proud of. Biffy thought of himself as a sophisticated, yet down to earth cat- about-town. Biffy's best friends were Mr Marple, the large ginger tom from two doors down and Robbie the West Highland terrier from across the road. Mr Marple, who was just called Marple by his friends, happened to be owned by two people who were huge Agatha Christie fans. They also had a gold fish called Poirot and a Budgie called Agatha. Robbie was rumoured to be a distant cousin of Greyfriars Bobby, the famous 19th century Edinburgh dog who stayed by his master's grave and was looked after by the local people in recognition of his loyalty. Biffy thought that Robbie had started this rumour himself. Meanwhile, out in space, a small fleet of spaceships from the planet Mars had managed to sneak up and hide behind the moon in preparation for a raid on Earth to steal lots of cheese from a cheese festival in Cheddar, England. During the Martians attempt to land a sudden fault with the rocket motors on board the Martian flagship ship, the Zulupapalulu, forces it to make an emergency landing close to where Biffy and his friends were having their afternoon nap. Investigating the disturbance Biffy and his friends discover that the Martians are Mice and overhear their dastardly plans. After several comic adventures Biffy and his friends manage to steal 3 of the Martian mice's hover scooters and find their main landing site. Using his generous for invention, Biffy constructs a make-shift catapult and using bits of cheese as ammunition takes on the mice in a climactic battle and saves the day.