The steamship Renfrew is on its journey from Tilbury to Australia, having just weighed anchor in Colombia, Sri Lanka, about to cross the equator – the so-called “line”. On board are a collection of passengers, most notably Dr Hector Drange, his daughter Astra and his nephew/secretary Leonard. Drange is heading to Australia with his latest discovery, a method of detecting uranium – something that would be worth a fortune…

Astra is also due to come into a fortune, the chance to break the shackles from her father – but on the eve of that money being inherited, as the boat crosses the line, she is found dead in her cabin. At first is seems that she committed suicide, having stabbed herself with the knife found under the body. After all, the cabin was locked and bolted from the inside. One slight problem – the knife was too big to make the stab wound…

Right, back from holiday and with a bucketload of reviews to write, so I’ll try and be even briefer than usual. Of course, writing that makes things longer than usual, so let’s shut up about that and get on with the book.

Cecil M Wills (Maitland Cecil Melville Wills) wrote twenty-six mystery novels, some (not this) with Inspector Boscobell, some with Superintendent Ellerdine and some (like this) being standalone. This makes sense – after all, how often will a murder happen on a boat when a famous detective just happens to be on board? Ahem.

So, a proper locked room mystery – I hadn’t realised this when I picked the book up – but this isn’t one for afficionados of that genre, because it’s hardly the crux of the plot. Indeed, the solution as to the “how” is given before the halfway point, and it’s a pretty straightforward one. But it is also a decent enough whodunnit with a clue or two.

It suffers, perhaps, from a lack of convincing suspects – I thought the killer stood out a bit, in the final third at least – but the cruise-ship setting is well done, and once again convinces me never to take a cruise of this ilk. Any cruise that requires you to pack a fancy dress costume isn’t for me…

Wills’ books have been variable for me – this is the fifth one that I’ve read – but this is one of the better ones, alongside Midsummer Murder and The Dead Voice. Sorry, there are no plans that I know of for reprints and you’ll almost certainly not going to be able to find a copy, but if you do see a cheap one, you could do a lot worse than this one.