This is an odd one, but it cements the transition for me. Cassandra‘s back–if you never watched “The End of the World,” the second episode in Season One, you missed Cassandra–and she’s still determined to survive no matter what. Rose has accepted the new Doctor, but in this story the viewer sees that the Doctor really does know Rose, no matter what happens. Also, lovely bit of character switching and the Face of Boe. I think this with “The Christmas Invasion” cements the transition. Well, this and the fact that Tennant is outstanding as the Doctor.
Robena’s book Desert Exposure is free on Amazon Kindle today.
ETA: Also Tamsin’s book: