Summary: The Doctor is not at all pleased when Barbara and Ian force their way into the TARDIS without being invited.
How dare they? Barging into the TARDIS without a by your leave! Accusing him of holding his own granddaughter prisoner, of all things! Why couldn’t they have minded their own business? The Doctor was displeased; one might even say he was in high dudgeon. Indeed, there was a word that should never have gone out of fashion. Humans were so flighty, even their language seemed to change constantly.
Perhaps it was his own fault; he shouldn’t have allowed Susan to attend the local school, shouldn’t have remained in one place so long.