You have a limited time, and during this time you have to collect as much gold and gems as possible.
This gold and gems are carried away by the mice, and you need to aim the hook carefully to catch and reel them in.
Just beware of the digger miner. He doesn't like it when you steal their gold, and he'll cut your rope if he can!
Every time you get gold or a gem, you get extra time, and as you progress, the game will become more difficult.
So do your best to earn as many points as possible!