Doctor Who: Valhalla

This is unusual in being a 7th Doctor story not featuring any companion - it's apparently set shortly before the TV Movie, rather than during the main BF continuity. The Doctor arrives on a run-down colony world, apparently seeking to retire from adventure and reflecting sadly on all the companions that have left him over the years.

Of course, it's not long before monsters turn up, and the story moves into more familiar territory. Certainly, it's hard to see this working with any other Doctor, and there's something of a sense of the impending changing of the guard. But, ultimately, it's not enough to raise this slow-paced story above the merely average.