(out of 5)
|* * *|
A surprisingly mediocre episode for a major mid-season two parter. It doesn't provide anything beyond your regular Star Trek time paradox that has it's roots in the 20th century in the same pattern as 'City on the Edge of Forever' from the Original Series. There is no novelty left here, so any entertainment value comes from the story, which is unfortunately fairly predictable. The biggest point of interest is the further evolution of the Doctor, which has an impact on story lines in the future.