There are some interesting ideas in Underworld. The Time Lords being gods to an ancient species who destroyed themselves and now seek a new home to repopulate their race is an intriguing concept. Set at the fringes of the known universe, the story also deals with stellar phenomena like planets forming within nebulae, and a second ship of colonists who have survived beneath the surface, only to serve as a slave race for a computer called the Oracle.
Sadly, it is at this point that the story takes a turn for the dull. Part 1 is quite exciting, I like the industrial design and the production values are good. But once beneath the surface, it’s a tedious sequence of chases through caves while the two groups fight it out. They don’t even use real caves, the vast majority of the episodes take place on a chroma key backdrop with some caves pasted in afterwards. It doesn’t look good.
It’s not really explained how the Oracle came to be, nor from where the two robot guards originated. I like the idea of mission directives becoming ancient prophecies over thousands of years, but it isn’t well explored, nor is the idea of the Time Lords as gods, or the Doctor attempting to correct the mistakes of his people. Tricking the Oracle by swapping out the canisters with the explosives is also a pretty cheap way to end the story. There’s an attempt to tie the events into mythology, but it falls flat.
It’s not that there’s nothing to like, it’s just that the good ideas are not expanded upon satisfyingly, and the story somehow manages to drag even with just four parts. Some of it is good, but I was pretty bored in the middle.