Starring Tom Baker as Doctor Who he's given a quest by the White Guardian to track down the six constituent parts of the Key to Time. Thus, each of the six stories sees the Doctor and Mary Tamm's Romana hunting down one of the segments.
In many ways showing the highs and the lows of Doctor Who in the late 1970s, the Key To Time has some very distinct highlights. The Pirate Planet, for instance, is a cracking story in its own right (written by Douglas Adams), and we're also fans of The Androids Of Tara and the story that wraps the saga up, The Armageddon Factor. Ironically, it all gets off to a low start with the tepid The Ribos Operation, while The Power Of Kroll is just silly. Even by Doctor Who standards!
Nonetheless, this is a significant and very worthy entry in the Doctor Who canon, with both Tamm and Baker on top form. There's also some cracking episodes within the Key to Time, and a real feeling of risks being taken with a long-running property. --Jon Foster