Very Good Early Character Development

After the first few stories mainly focused on the characters of Ian and Barbara, this story is much more representative of The Doctor.

The Doctor has his first great speech in the show which really solidifies him as a wanderer in time looking for answers to questions. Susan is also shown as being more alien which sadly doesn't appear again as a concept until The Sensorites.

Despite the story at times feeling confusing, after rewatches it slowly gets more understandable. I think the story also benefits from it's shorter length giving just the right amount of time to have a TARDIS-bound story. My only gripe is how for most of the story Barbara is given the role of housewife to the TARDIS, she does have some tension with The Doctor but does seem to just be there.