Jacob Black's terrifying transformation into a werewolf in The Twilight Saga: New Moon has been unveiled in full for the first time.

Jacob, played by Taylor Lautner, is forced to transform when Bella Swan (Kristen Stewart) angers the rest of the wolf pack.

In the clip, Jacob runs to save Bella, who is still devastated from the sudden departure of her vampire love Edward Cullen (Robert Pattinson).