The Wolf and the Thief by whoson1st is great. It’s something that every fanfiction-reading Doctor Who fan should read some time. The plot is canon with some deviations that always have a good reason behind them; the writing style is refreshingly flexible; the grammar is excellent.
All of this, however, pales before the character development. The main focus of this story is on deconstruction and reconstruction of the Doctor’s personality. Let’s face it, the Doctor has issues, both in how he deals with himself and with his companions. The inherent conflict of the character is one of the main reasons behind the show’s popularity, and whoson1st takes that conflict apart and builds it back together through Rose.
Excellent characterization, no retconning, and just plain old great writing—highly recommended.