Rat Attack! is an arcade-style puzzle game for the Nintendo 64 in 2000. A pair of lab rats, Washington and Jefferson, were sent into space aboard a rocket in an experiment. However, after some incident in space, the rats had been mutated and gained super-intelligence. Over forty years on, they have returned to earth and immediately commenced with plans for world domination, amassing a huge army of rats with instructions to destroy everything in sight.

The felines of the world band together to combat this menace forming a group called the 'Scratch Cats'. Headed by cat genius Professor Rex Julius, they fight off these rats with several of his inventions which eliminate the rats in a humane way.

Professor Rex Julius sent his special agent Pearl to investigate, but Washington and Jefferson managed to capture her, imprisoning her within a laser cage guarded by giant robots.

They go from location to location, cleaning up the rats. Along the way, they meet another mysterious cat in the clutches of King Scarab.

At the end of the game, with all the areas saved from the ravaging rat army, the Scratch Cats manage to defeat Washington and Jefferson in a showdown in their space base. However, the duo manage to escape after their defeat, Julius afterwards revealing that they also taken King Scarab with them.