This series (really two related series—it should have been Allison and Will then Lilia and Treze, like the books) deserves a full review. Some notes after finishing the final episode:
The first season is more or less unreservedly good; pretty, lilting intro, interesting WWI-era technology European-styled alternate world with plenty of interesting stuff going on, loads-of-fun characters, high adventure, and a dose of drama without too much serious. Allison (it is named after her, after all) steals the show as a heroine with far more guts and drive than brains who drags the somewhat resigned-t0-his-fate Will along for the ride on all manner of crazy adventures.
That said, it’s really an ensemble show, with several other characters (all of them older than the main duo) having plenty of significant stuff to do. They’re a little older than they seem, by the way—I’d have guessed 15, but based on the ages mentioned explicitly later, they’re probably 16 at the start working their way up to 18 by the end.
The stories are told in 4-episode arcs (presumably corresponding to the light novels it’s based on), which keeps things lively and compartmentalized. All three in the first season are fun—some mystery, some characters-trying-to-figure-out-what-the-scheme-is sleuthing, sufficient action, and a bit of drama and character development.
It goes out of its way to stay fun and “gentle”, with a very low body count and the main characters working very hard at not killing anybody (and the series going out of its way to help them). Which is why it seems rather weird to throw in a violent bit of character revelation toward the end which I can’t mention in any detail whatsoever without blowing a major plot point. Still trying to figure out how to go about that with a full review.
The flaws are that the animation is occasionally noticeably weak, once in a while it goes a step too far in cleanly wrapping things up, and the final episode pulls a major character change that may or may not make sense—it skips 4 years—but either way we’re not given anywhere near enough information to have it make any sense at all. It also totally gyps the viewer out of the big kiss in the next-to-last episode, but that I can I suppose forgive (though it seemed completely unnecessary).
The second season, set 19 years later (15 after the last episode) and following Allison and her teenaged daughter is almost as good. Almost because it’s still got fun, adventure, some action, relatively involved plots, and though Lilia isn’t quite Allison since she seems to have inherited the worst parts of her parents’ personalities (dad’s tendency to panic and mom’s crazy streak and lack of brains) she’s plenty of fun. Treze is a little too competent to be as much fun as Will, but he’s got a good reason to be.
Fortunately Allison and the rest of the crew are still around and making a reasonable amount of trouble, so it’s not all about the kids. Also, Allison is a fantastically bad parent in just about every department which is somewhere between fun and making you feel sorry for Lilia. Again I’m not sure how to even discuss it without totally blowing a bunch of stuff plot wise, but there are major secrets about Lilia’s heritage that basically EVERYBODY but her are in on, and for no particularly good reason.
However, the series a couple of times whips out major “murky morals” reveals that don’t directly affect the plot in ANY way, but change major characters from being sympathetic to borderline evil. For NO reason I can figure. Now, I can fully understand “bound by duty, even when it is difficult”, but these go WAY beyond any of that as far as the series explains and into “Ok, that’s pointlessly heartless for NO reason at all.” territory to the point that it half-ruined it for me by sapping all sympathy from otherwise likable characters.
Even if I write that off as a bungled novel-to-anime adaptation issue or terrible writing, though, the last episode is one of the worst story-satisfaction disasters I have ever seen. And I’m an anime fan—we practically expect series to go to hell at the end.
Basically it tosses a significant and basically pointless reveal in toward the end for no reason, COMPLETELY skips at least one major character development point that had been set up from minute one of the season, and the end just plain doesn’t make sense. It could make sense, if they explained to us what the hell happened, but they don’t. In a series that is basically defined, plot-wise, by setting up involved plots with multiple parties working toward multiple ends and the main characters (and viewer) trying desperately to figure out what’s going on before it’s too late.
I literally couldn’t believe that there wasn’t an extra scene waiting after the credits that was going to have the end make at least some degree of sense, but no.
Such a disaster of jettisoned sub-plots I have not seen since Lain, and I’m not sure I’ve ever seen a series that left me so angry at the lack of a simple explanation for what happened off screen.
Still a lot of fun, but I almost wish I’d have just stopped watching at episode 12 of season 1—it’d have all been fun and satisfying then.