With the assistance of Tim Powers’s almost-superb The Anubis Gates, I have figured out a bit better why I like time-travel novels (and short stories and movies). It’s the puzzle-solving part of my brain at work.

That is, I like novels that play with the manipulation of information. I like novels that have genuinely bravura plot twists. (I won’t name any because I don’t want to ruin the experience for anyone else. Pace M. Night, part of the great pleasure of a twist novel is realizing that it is a twist novel, even before you have figured out the twist.) I like novels that scatter plot threads and characters like cards, only to gather them slowly together again with inexorable logic. I like novels that run through the same events from different perspectives.

All of these techniques have in common with the time travel novel their overdetermination. They have to satisfy significant logical constraints. Pieces of information do double or even triple duty. Details must coordinate with other details. Everything said by the nonexistent person must be recognizable, in hindsight, as a hallucination. The omissions in the earlier narrators’ stories must line up with the corrections in the later narrators’ stories. The gun over the mantel in plot thread one must be fired in plot thread three. The puzzling mind is pleasantly tickled by this secret undercurrent of structure.

The time travel genre is particularly conducive to this structural coherence because of its logical basis. The past must have been interacted with in a way that will result in the odd traces we in the future observe in puzzlement. (Or, conversely, the future must develop in such a way as to send back the bizzare phenomena we in the past are grappling with.) The interaction of a timeline with itself, skillfully done, tends naturally to create the kind of overlapping plot constraints that I find satisfying.

Thus, The Anubis Gates does, to my mind, a masterful job of glossing over all the unimportant bits of setup. The explanation for time travel makes no sense. It’s not supposed to. Powers just gets right into the thick of a bizzarely overlapped set of characters and events. And then he gradually pulls back the curtain, linking up first one and then another. Everything radiates out logically from the first unnatural interference with the fabric of time … it just takes quite a while, narratively speaking, to make all the connections link up. Some are brilliant—Dog-Face Joe, I must say, provides unexpected but quite elegant solutions to some old problems of sci-fi structuring.

Of course, as Steven has noted, the climax is quite difficult to follow. It’s also disappointing in the way that many time-travel novel climaxes are. Once everyone has met up and the odd logical loops have closed off, you’re left with fairly conventional devices and confrontations. People squaring off across time is a lot more interesting than people squaring off with guns and fisticuffs.

One other virtue of the novel, while we’re talking originality, is Powers’s choice not to make the villains omnipotent or all-threatening. They’re certainly villainous blackguards, but they’re driven as much by desparation as by malice. Not only does the choice actually make them feel more dangerous (in their confusion, they seem much more capable of malice towards our heroes than central casting bad guys would ), but it also gives the book an off-center, uneasy energy. The plot kicks forward, driven by impulsive decisions and contingent encounters, everyone crazily trying to make sense out of what’s going on before it kills them. All of which fits in nicely with that other classic time-travel theme: a sense of almost existential dislocation. Things happen that don’t make sense to the characters, and a raw, panicky feeling it is indeed.

One final thought. What is the deep fascination among sci-fi authors of time travel novels for the English Romantics? Powers riffs on Byron, almost unnecessarily. Hyperion and The Fall of Hyperion went on about Keats at quite ridiculous lengths. Dirk Gently played with Coleridge. Three times, as they say, is enemy action. What gives?