Time travel is fertile ground for any sci-fi series - some of TVs best episodes revolve around it - and it does not disappoint here. The writing, acting and special effects are good and an effort is made to make the sets approach at least near-believability. The Allen penchant for firework displays and blinking console props from previous series is present throughout and is somewhat annoying - Allen was a psychopathic cost-cutter. Special mention should be made for the time tunnel design and surrounding set.
In general, a fair series with many mediocre, yet entertaining, episodes . . . and some good ones.