It was clevr, fast and also quite spooky. A werewolf was loose in Victorian Scotland and the Doctor, Rose and Queen Victoria had to defeat it before it took control of the Royal family.
Most of the start is quite dark in a cellar with a strange man in the cage. Little did they know it was in actual werewolf. The spookiness of this episode is quite high.
At the end it leaves the impression the wolf did succeed when Queen Victoria has what looks like a bite mark.
All in all a cleverly plotted episode with mystery and a slap in the face answer.