This is a cracking read. It is not unique in its combination of Doctor Who and the whodunit genre: the episodes Robots of Death, Black Orchid and The Unicorn and the Wasp have all done it (the latter featuring Agatha Christie herself, no less). Even among the BBC Doctor Who books, there has been Five Little Aliens, a First Doctor adventure, though the companions, Polly and Ben, are the same as in this one.
I think this one works better than Ten Little Aliens (reissued last year for the 50th anniversary), which is over-egged, a bit arch, more plotty and with rather too many underdeveloped characters - excusable in this genre, perhaps, but it makes it more of an effort, rather than a pure pleasure.
Here you can just sit back and enjoy as the TARDIS lands in a fading hotel in space, just as a murder mystery game is starting...and (of course!) a very genuine murder is about to take place. I have always thought that Polly and Ben were the best double act of the Doctor's companions ever, and they play a very enjoyable and active part here. Patrick Troughton's Doctor is very fondly remembered, and here he even gets to wear drag!
A superb read - light but very engaging. Joy Swift's Original Murder Weekends frequently feature an actor who is a massive fan of Patrick Troughton's Doctor. I must recommend this to him (though I bet he's already got it!)...