There's not a lot to this plot, but what's there is done marvelously. It's a great companion introduction for Vicki, with some compelling character conflict over Barbara's well-intentioned but disastrous killing of Sandy. It was also nice to see the Doctor feeling morose after Susan's departure -- it gives even more emotional weight to the end of the previous story. The evil plot, though, was very Scooby-Doo, and I don't just mean the costume; Bennett was literally the only other person on the planet. It isn't exactly Agatha Christie. It's a fun one to watch, though!

an overall decent introduction to a new companion but a pretty lacklustre story plot wise. bonus points for costume design and the doctor being a complete gremlin

A gem of a two parter. Being shorter than most stories makes this such a tight and strong and easy watch. It's also the debut of Victoria as a companion, who in my opinion is more enjoyable to watch than Susan.

• I've always much enjoyed Vicki as a companion and her introduction solidifies that
• It perfectly takes use of its time and doesn't prolong it any longer than it should
• My literal only gripe is the small minor details that could help piece everything together, like hints that other crew members were still alive or there being signs of the planet's original inhabitants being killed. Something to level up the world-buildin
• This is a story that feels a little predictable, but there's nothing wrong with the obvious incoming twist it works well, and it earns it
• It's a story that captures why I like the 1, characterised beautifully

I like this serial. It benefits from being on the shorter side. The story is concise but interesting. The twist reveal is  set up nicely and done very well.

I immediately like Vicki, and not just because she looks like my favourite cousin. This is a great introductory episode for a new companion. I love how she immediately trusts the Doctor, how much she cares for the local wildlife, and her willingness to forgive Barbara despite killing her pet.

Unlike most classic stories yet to come, this serial doesn't immediately forget about Susan. The Doctor is clearly still feeling her loss. I appreciate that.