An overlooked little gem of a story.

The TARDIS malfunctions leaving our crew disoriented and paranoid in what is essentially a bottle episode(s). I think the writing is interesting, keeping the mystery of what's happening intriguing and suspenseful. The direction is fantastic as well. The blocking in particular is great and really heightens the sense of paranoia and dread. I love how creepy it is when Susan wakes up in the background (Carole Anne Ford's physical acting is tremendous here) and the shot of Ian on the floor one moment, then the next he's standing rigid in the back of shot.

The second episode sadly can't maintain the unnerving sense from the first episode. Although this is likely because the second episode is less about establishing the creepiness of the situation, and more about resolving the plot. Some may find the resolution being about a faulty spring in the TARDIS a little underwhelming. It doesn't bother me though, because the solution was always going to be some malfunction in the TARDIS. For me what the solution actually is, isn't as important as how we get to the solution. I found are heroes arguing and then working together to realise what to do very compelling here, so I can easily forgive the problem actually being just a single spring not working.

The second episode does get to really move Barbara to the forefront though, and she's great here. Of our two human companions, Barbara has thus far been a little overshadowed by Ian, who gets to play the more traditional hero. But it's Barbara's intuition here that allows the Doctor to see what's happening. Barbara's confrontations with the Doctor are great, and I must shout out the performances of both Jacqueline Hill and William Hartnell.

I find this story to be a wonderful change of pace for the show, that is effective in setting it's tone. Add in some wonderful acting and I find myself having a great time watching this story.