Brian Lumley's Titus Crow is actually a compilation of two novellas: "The Burrowers Beneath" and "The Transition of Titus Crow." They connect as larger texts, in that the events from one lead directly into the other, but there is a rather rapid shift in subject, in tone, and somewhat in style between the two.
"The Burrowers Beneath" is a horror/fantasy story, that wears its Lovecraftian influences very prominently. The titular character, Titus Crow, stumbles onto a Chthullian world of tentacled, menacing ur-creatures bent on enslaving humanity and ruling the world. The narration is provided by Henri-Laurent de Marigny, his sidekick from another tradition entirely, that of the Sherlock Holmes and Dr. Watson. It's a slight genre mashing, which becomes more evident later, when they become involved with the global efforts to limit the advances of Chthullian forces. It does well in capturing the general mood of the Lovecraft horror stories, and at its best has a great "horror" atmosphere. At its worst, it's hampered by bland characters (de Marigny is a little TOO like Watson in that department, and Crow himself is little better), ex machina intervention, and a climax that seems separate from its stakes: the novella spends a great of time explaining that the battle for control of the planet has reached a desperate turning point, but the end fight is between the two main characters and low-level broodlings.
"The Transition of Titus Crow" suffers from many of the same problems--climax has been jettisoned to make room for exposition; the character roster now includes Tiania, the innocent, beautiful girl Not of This World, who comes off a little cliched; and random earthquakes, last minute escapes, and intervening godly intelligences are part of the norm--all arguably forgiveable, given the genre Lumley has chosen to write in. What's interesting is that the good elements have shifted considerably, arguably to another genre entirely. Without giving away too much of the previous story, Titus Crow is taken on an adventure through time and space, so it's less of a novel as a series of vignettes. As one of the blurbs on the back mentions, it is as much H. G. Wells as Lovecraft at this point, as Titus outwits dinosaurs, is resurrected by robots, flees from monsters beyond time (okay, there's still some Lovecraft), and meets the woman of his dreams in the place of his dreams. There's a real sense of adventure to the second story, and Lumley deserves full credit for that.
Essentially, then, it's two stories for the price of one, but from an author who seems better at capturing locale and mood than character. If you're a fan of Lovecraft, you need to check this out-- but whether you'll like it another matter. I think I've mentioned before that I sat in on a cyberpunk class last term, and the class started at Frankenstein, then jumped to the genre's inception in the 1980s. I'd like to posit the subgenre of Lovecraft themed fantasy as a missing link between the two. It's clearly got some of the same themes: they're male oriented, nonheroic, and based on the accumulation of knowledge and power. More importantly, the accumulation of knowledge of power is portrayed as ambiguous at best: as in Frankenstein, there's a definite strain of "Man is not meant to know." It needs some ironing out, but I think there's a definite case to be made for adding these works to the pre-cyberpunk canon.
The question at hand, though, is whether "Titus Crow" is really a Lovecraft story. In the cyberpunk class, we looked at the movie "the Matrix," which featured a lot of definitive cyberpunk traits: it was big on technology, yet with a retro spin, it had hyper masculine and feminine characters, it was slick and smooth, it featured man bonding with machine. And yet, it wasn't quite cyberpunk, for the simple reason that a cyberpunk main character is never the one--he is one of many. He does not play the hero. Likewise, the Lovecraftian main hero may attempt to play the hero, but he can't win anything beyond a pyrrhic victory--the forces of evil are too strong, and the corruption that comes with the knowledge necessary to face them is too absolute. And yet it Titus Crow, we see in the first story a massive, global organization centered around fighting the Cthonic forces, and in the second, we see Elysians, the good, equally powerful counterparts to the Cthonians. I'm somewhat interested in the symmetry that this depiction presents, but... I think it might cross the line between bending the rules of the genre and breaking them.
Final Verdict: A flawed book, but it raises interesting questions--if you're predisposed to these sorts of questions to begin with.