After taking the good Doctor into some very dark territory with "The Waters of Mars," Russell T. Davies returns the Doctor back to his roots with "The End of Time, Part One," the first half of David Tennant's final story as the Tenth Doctor. From the very beginning of the episode, Davies intends to create a memorable story to give Tennant a fond farewell. And the story really is brilliant, exciting, wacky, and scary in the tradition of classic "Doctor Who." The cast and crew do a fantastic job of creating this amazing story, preparing us for the second half of the story, which promises to give Tennant an epic, fantastic farewell. While some may find it too outlandish, it does so with great fun and excitement, making it worthwhile. And the cliffhanger is the biggest, most exciting one yet, ending the show on a double-whammy! Longtime fans will surely love it! Allons-y! Grade: A+