I struggle a bit with the eight parters. The story is often far too thinly spread out and the plot advances at a glacial pace until it's all wrapped up in episodes seven and eight. This one is slightly different, though, as it neatly separates into two semi-stories. The first sees the "Doctor" (Jon Pertwee) and "Liz" (Caroline John) drafted in by the "Brigadier" (Nicholas Courtney) to investigate ver mais...