This season is a real lucky dip - this time, a fun and original horror story!

The Doctor doesn't spend much time in the spotlight during this story, and is in the library for most of the story - unfortunately this means he gets little characterisation and is a little dull. However, we get to see Leela in action, and how she's changed so much that she doesn't need the Doctor. She uses her knowledge and hunting skills to beat the shadow demon and leads the story very well, with some very humorous moments to keep it lighthearted like the Williams' Era was meant to be, becoming more family-friendly. I'm a bit disappointed that K-9 didn't have any time in this audio - I was expecting this series to be all of them, and whilst the TV series had to write K-9 out due to errors with production, the audios don't deal with that.

The monster in this story reminded me immediately of the Vashta Nerada but a lot more generic. I think something that works is a lot of set up for the creature - not getting much time, and just killing people subtly throughout before the side characters are tricked into releasing the monster. However, once it is released, there's nothing standout about this.

Caversham Manor was a great setting for this story, being isolated from the TARDIS and constantly raining - as England ever is. The house is utilised really well, and we get to explore it in many different forms, before having one final standoff on many different levels of the grand hall. It's strange how a place so big can feel so claustrophobic.

Is it weird that the Caversham Society is comprised of two people, and they hired out a hall manor for them? I think so. The characters all felt realistic, and tied in well to the plot, but there were some moments which felt incredibly unearned, such as the plot twist at the end of the story when it turned out Mortlake was working for the demon the whole time - but there are some good shocking moments, as Caversham is said to have killed himself - and we all think that he was ill, but we get to learn that he was a hero.

I do think that something that would've improved this mystery is if the plot twists were hinted at instead of suddenly revealing themselves without set up. On the whole though, one of the best Fourth Doctor Adventures that I've heard so far (I think that Justin Richards is probably the best writer for this range, also giving us The Renaissance Man).