The Golden Compass (movie)
Lord Asriel has found something called "dust" that separates us and another universe.  People do not believe this idea.  The Magistrate, a very large and strong group, try to kill him by poisoning his drink.  Lyra, his niece, was playing, heard someone coming, hid, and saw a priest try to poison the drink.  She then ran out and saved Asriel before he could drink.  Asriel later goes to the North Pole to find this dust.