The famous clock-maker Oscar repairs Balthazar’s clock and finds inside the mouse Igor who spends his whole life inside clocks. They became friends but Igor wanders away who spends his whole life inside clocks. They become friends but Igor wanders away in search for clocks. Professor Balthazar is attending a congress in London when a catastrophe happens: Big Ben, clock above all clocks stops working .The whole of Great Britain is excited.Master Oscar discovers the mouse Igor inside Big Ben, and it works once again. The grateful British permit Igor to live for ever inside Big Ben, which was his life’s dream.