The Silurians were not the only race of subterranean reptiles hibernating underground – a similar species, living in a fault line under the ocean, have now awoken, and are once again a bit annoyed that apes are running the planet, and want it back.
The “sea devils” are not very interesting creatures, really just a similar take on the Silurians, except they can swim and they have (admittedly pretty cool) heat guns. The plot takes too long to get anywhere interesting, and even the reappearance of the Master does little to help. If anything, the prison escape parts of the story slow everything down; and, if I’m being picky, the Master’s motives for his involvement are paper-thin at best.
That said, I liked the fact that the Doctor and the Master have a sword fight and chase each other in jet skis, and that he pulls his rubber mask trick at the end and escapes again. He’s such a devious cad! There’s also lots of footage of boats and explosions, and apparently the Royal Navy was involved in its production in some way, which shows.
But, alas, this was all very slow and boring. It was too long and the drama regularly fell flat. In addition, I must mention the music. I can accept “synthy” as a style, but this has some of the worst music I have ever heard in a television show – often so bad that it blurs the line between music and sound effects, regularly distracting me from what’s actually happening, stylistically ill-fitting with the modern day setting and tone. Did somebody give the BBC sound engineer a keyboard and say “go nuts”? Because that’s what it sounds like. Zzzzappp!! Brrrpp!!! CHNGGG!!!! The whole way through. Maddening.
I’ve noticed some sexist attitudes lately, particularly apparent towards Jo. Although she rescues people in this story (including the Doctor), she’s treated like a child (literally called one at one point) and the Doctor continues to do that patronising thing where he holds her chin and tells her to run along or whatever.
Nothing else about this was memorable, except for an historic moment, as the Doctor uses his sonic screwdriver for something other than removing screws! It’s apparently able to detect mines, and explode them, and later able to burn open a locked door. How handy!