I love this episode. It's one of my favorites. Here we see David Tennant for the first time as the tenth doctor( excluding the thirty seconds at the end of the parting of the ways). And he is brilliant. He is totally natural. The rest of the cast are very good as well. Billie Piper is also very natural as the doctor companion. The script is good, with some brilliant lines (see quotes page). The pass of the episode is good, with a good lot of action ( the crash landing tardis, the attack of the father Christmases and the Christmas tree, the sword fight..) but not too much, and there is no excessive violence. In fact there is practically no violence, in less you include the sword fight, and even there everything is kept proper: no blood. We also hear what I think are is the first reference to Torchwood. The episode keeps up until the very end To sum it up, i say go and watch this episode as soon as you can.