"Robot" - Fun for the introduction of the new Fourth Doctor, not so good otherwise. As is often the case for this bare-budget show, the vision of the writers exceeds the ability to execute well on screen. The titular opponent here is a rather clunky collection of bits initially, and sadly the script decides to have it inexplicably grow to huge proportions, resulting in the usual bad blue-screening effect. The plotline is a fairly generic "superior scientists decide to become munificent dictators" story, with a dash of "robot develops human feelings" thrown in. Nothing particularly special.
This one's mainly good for seeing Tom Baker immediately jump into the role of the Doctor, hitting the ground running. Sladen's Sarah Jane meshes well with the new lead, and of course almost any time with the Brigadier is going to be good. But otherwise, not much of a story. Two stars.
"The Ark In Space" - I kind of like this one. It's got a lot of typical elements - Sarah stumbling her way into rescue situations, the suspicious commander, alien mental takeovers, noble sacrifices. There's not really much new here, but it's just a pretty basic, competent story. So it gets a basic rating of three stars.
"The Sontaran Experiment" - Filler. Just a two-parter, this one is mostly interesting for being set completely on location - and a location that isn't that same quarry they used for everything back then (like in the very next storyline, for example). However, the storyline mostly consists of people falling into rocky pits and climbing back out, and scenes of prisoners being tortured as scientific experiments. Unfortunately, the script has an entire galactic invasion waiting on the Sontaran to finish running an experiment to see how much weight a pair of humans can hold up - and then when the experiment is halted, the invasion is called off! Uh, what?
Despite a few good moments (like the fear experiment on Sarah Jane), and the different setting, this one really doesn't have much going for it. It is what it is - filler. Two stars.
"Genesis Of The Daleks" - Ah, but this one on the other hand....yeah, it's good. A definite grim atmosphere, from the battlefield scenes at the very start to the Nazi-invoking Kaled uniforms to the destruction of the Thal dome to the mutants - this one isn't particularly jolly, despite Baker's already perfected mugging. Yeah, there's a few strange moments, such as the giant clam attack (?), and some of the cliffhangers don't make much sense (in particular, Sarah falls off a scaffolding at the end of one episode, only to land on a platform just below at the start of the next one).
There's a great introduction to Davros, the Dalek creator here - sometimes a coldly calculating villian, others a shrieking personification of his Dalek creations. The weak point here, as usually was with the early stories, is the Daleks themselves - I never found them overly scary in their early clunky form. This was fixed in later stories, where they get the ability to hover around and move with some speed. And to be fair, the Daleks don't actually do a lot of the work here - it's mostly Davros and his thugs that do the damage.
I really can't give this one less than five stars - there's a bit of padding here and there, but this is about as good as Doctor Who got at this point in its life.
"Revenge Of The Cybermen" - Back to the set of "The Ark In Space", but this time dealing with an approaching asteroid of gold - a threat to the gold-fearing Cybermen. Only - well, I don't remember anyone actually successfully using gold as a weapon here. The Doctor and Harry try, but they don't end up having any success. This story tries a bit too much with traitors on the various sides - I'm not really that much into watching the political situation on an underground asteroid. Suffice it to say that no one's master plan here was really thought through very well.
I do like the Doctor's response to learning that Harry had caused a cave-in and almost detonated a bomb, though - "Harry Sullivan is an idiot!" Cybermats - not so much. This one gets three stars also for a few good moments.