The advantage that this first episode has over Fury from the Deep's one is that at no point do you get upset with any of the supporting cast, since this episode only has the Doctor, Jamie, and a robot for the majority of it. We see (or rather hear) some exploration of a spaceship called the Silver Carrier, much of it conducted in virtual silence -- which is a bit of a problem for an episode that only exists in audio format. But you get a sense of tension and calm at the same time (if that makes sense) as the episode indicates that things are slowly but surely going to go wrong. And with the (somewhat) menacing presence of the Servo Robot and the sudden course correction leading to the Doctor getting a pretty severe concussion, the stakes get even higher, as there's a sense of helplessness pervading the situation. It's an effective feeling -- so much so that it feels like a violation when in the last few minutes we cut to the crew of a space station, the eponymous Wheel in Space. But even then we're introduced to danger, as the crew believes that no one's on board and it's a hazard, so they're going to blow it up with an x-ray laser.
Episode 2 gives us a more proper introduction to the Wheel's personnel, and it appears to be your standard international crew manning an isolated base. The Doctor's still unconscious for this episode (Troughton's on vacation again), so Jamie has to try and bluff his way through the situation -- except he's not very good at it. But look! it's the first use of "John Smith" as an alias for the Doctor -- a name which Jamie spies on a piece of medical equipment. There's also some nice attention to detail in this scene and the following, as Doctor Gemma Corwyn reports the oddities of Jamie's behavior to the base's commander, Jarvis Bennett -- his blood pressure suggesting he hasn't been in space long, and his abandonment of a glass of water showing he hasn't been trained to be in space both being nice, reasonably scientific-feeling touches (the irony of this will become apparent in later episodes). And we also get our first introduction to Zoe, described as the Wheel's librarian, but interestingly she's shown to be somewhat unlikeable, with a computer-like characterization implying a lack of understanding of humanity and pragmatic cues. Or, as Jamie puts it, "just you watch your lip or I'll put you across my knee and larrup you." ("Oh, this is going to be fun! I shall learn a lot from you," Zoe replies.)
We also have the mystery of the floating eggs that we saw leave the Silver Carrier last episode, which seemed to penetrate the hull of the Wheel. Bennett (who's a bit gruff and paranoid, but not nearly as one-note as Robson was), is alarmed enough by small drops in pressure and similar incidents to order that the Silver Carrier be destroyed anyway -- which is a bit of a problem for Jamie, as the TARDIS is still on board it. And while that's going on, those eggs appear to be getting bigger, revealing a humanoid figure inside, one of which punches out of one of the eggs with a silver fist...