“I was going to put a spoiler warning at the top of this, even though I usually don’t, because it seemed like an episode where much of the appeal would be undermined by knowing all the surprises from the outset. As it turns out, the opposite is true: it’s better the second time. Nevertheless, maybe don’t read this until you’ve seen the episode.”
“If you can’t appreciate and relate at least a little bit to a story where the people you work for seem to view your most basic human needs as an unwelcome expense…you just might be one of the suits.”
“Things in ‘Knock Knock’ are a little bit magic because it’s a horror film packed into a Doctor Who episode, and almost every horror film is at least a little bit magic.”
“It’s the Doctor and his companion righting wrongs in a worthwhile, thorough, and satisfying way. One can imagine the churl who’d object to any of this, but one cannot agree with him, nor quite respect him.”
A small cast works well together to tell a simple monster story, reintroduce us to the TARDIS, provide a good jumping-on point for any new viewers out there, and give the longtime fans some Easter eggs right before the holiday.