Fantastic Voyage

Four men and one woman reduced to a microscopic fraction of their original size, boarding a miniaturized atomic sub and being injected into a dying man's cartoid artery. Fighting their way past giant antibodies, passing through the heart itself, entering the inner ear where even the slightest sound would destroy them, battling relentlessly into the cranium. Their objective, to reach a blood clot and destroy it with the piercing rays of a laser gun. At stake... the fate of the entire world.