I don't think it's a brilliant introduction to Jo. I also have reservations about the plot, which I remember not understanding, and the doll, which I understand was terrifying back in 1971, but now is completely appalling. Neither am I a fan of the Time Lords as they appear from this story onwards. Roger Delgado is a revelatory addition to the series (even if, despite it being in the original 1963 plans, I'm still not sure that the Doctor needs an arch-nemesis), but the bowler-hatted buffoon at the start is an embarrassment. Smug is a word that too often comes to mind when I think of this era of the show, which is really unfortunate. I wish I liked it more than I do.

I know this is a favourite for many people, not least Jon himself. And it's good. I just don't think it's great.

I do love this story personally, but it really does have its issues. Liz Shaw's offscreen departure is pretty terrible, and it's an equally poor introduction for Jo Grant, who, while not quite the hopeless ditz a lot of people make her out to be, is still a far cry from the amazing, self-sufficient companion she would come to be by the end of her run. There's also the horrific overuse of ugly CSO effects, the really dumb and out-of-nowhere resolution to the Nestene's plan (how did it not occur to the Master until the last possible moment that the Nestene may not be able to tell the difference between him and humans?), and the unfortunate racial caricaturing of Tony. Plus, while on the whole I love the creative use of the Nestene's ability to control plastic (something no other piece of media featuring the Nestene Consciousness has ever been able to match), the killer phone cord really is a step too far, and makes for a pretty ridiculous and poor third episode cliffhanger.