The latest entry in Terry Pratchett’s sprawling Discworld series, Raising Steam, is an example of what I call the “innovation” series-within-the-series. Just like there are sets of books that focus on specific characters and areas of the Discworld, there’s an increasingly large set of books that take on specific technological innovations entering the fabric of Discworld society.

We’ve seen this as far back as 1990’s Moving Pictures (in which the movie industry hit the Discworld) and 1994’s Soul Music (rock and roll, or as Pratchett calls it, “music with rocks in it”). Recently, Pratchett seems to be on a roll with this type of narrative, having introduced the character Moist Von Lipwig and then covered, in relatively short order, the postal system (Going Postal), banking (Making Money) and now mass transportation in the series’ latest addition, Raising Steam.

When a young engineer creates the first steam engine, it doesn’t take long before the first steam train is chugging along, to the great delight of Ankh-Morpork’s residents. A consortium of the city’s most powerful citizens, including long-time tyrant Lord Havelock Vetinari, Harry King and (of course) Moist von Lipwig, quickly get involved in the creation and rapid expansion of a railway system. Suddenly, areas of the Disc that were previously weeks or months of travel away from the city can be reached quickly and conveniently.

And so, the Disc changes again…

I’ve been a fan of these books since way back. As with any long series, there are some great books and some less than great ones. I’ve been reading these books for over 25 years, and there have been some slumps, but even the weaker entries in the series are usually fun for fans, if only because it’s always so great to visit this setting and see these characters again.

Unfortunately, in the case of Raising Steam, I fear that we’ve reached a low point in the series. I can’t say to what extent this can be attributed to Sir Terry’s condition (he was diagnosed with Alzheimer’s a few years back) but I believe at least one change related to this may be affecting the newer books: I understand the author currently writes by dictating to his assistant or using speech recognition software. Raising Steam has a noticeably different style from earlier entries in the series: less tightly written, more meandering, almost conversational at times. There are sections and paragraphs that go on too long. Some of it has the distinct “sit a spell and listen” tone of someone telling a long, rambling story  It’s just not as crisp as it used to be.

Worst of all, and this is the first time I’ve noticed this, Pratchett’s beloved characters are starting to blend together. In the past, you could open any of his novels, read a random bit of dialogue, and it’s likely that a regular reader would be able to identify which character said what. Raising Steam is the first time I’ve felt that didn’t work. Strong, long-time characters like Captain Vimes and Lord Vetinari feel almost faceless and interchangeable. Even Vetinari whipping out a classic line like “Don’t let me detain you” didn’t help. I can’t tell you, as someone who’s been reading these books for almost 30 years, how utterly disappointing this was.

So. Positives. Yes, there are a few good jokes, and yes, it’s interesting to see the Disc change again. The broad looks at areas of the Disc we hadn’t seen before are nice. The goblin story line continues to develop. There are some interesting revelations late in the novel.

Still, putting it all together, I unfortunately can’t recommend Raising Steam to anyone except the most fervid fans of the series. It’s too long-winded. It meanders and overstays its welcome. Worst of all, several characters feel like shadows of their old selves. I hate to say it, but it feels as if the Discworld series is, at long last, starting to lose steam.