Michael Flynn sets his characters adrift in Lodestar, the third volume of his ambitious future history series, spinning them about in a series of political maneuvers and mid-life crises.

Although the book makes room for a host of important plot and character developments, the degree to which this installment will satisfy readers will depend on how excited they are about the series as a whole.

So far, Flynn's storyline has relied on the ambitions of Mariesa van Huyten, an industrialist heiress determined to drag humanity into the solar system, for narrative force.

The complication arises when she realizes that she'll have to establish her own space program to launch the system.

Throughout the course of the book and its sequel, Rogue Star, she does just that, following a Byzantine plan to both build the technology that will explore space and shape the cultural climate that will support her other efforts.

Van Huyten tries to control every contingency, even manipulating young poets and artists to provide "inspiration." Several of her pawns grow to resent this, eventually becoming her worst enemies.

As Lodestar opens, van Huyten faces her 60th birthday powerless, stripped of her role as head of the family corporation and trying to influence events from the sidelines.

As she searches for a renewed sense of purpose, her plans remain in the hands of her followers while the students she influenced approach the prime of their careers.

The story is complicated, and each plot and subplot is closely connected.

There's a strong sense of consequences as virtually every character -- even astronaut cadet Jacinto Rosario, who was only a baby when the grand plan began -- is influenced by the changes Van Huyten Industries has wrought upon the world.

There's so much to account for that the narrative sometimes slows to a crawl.

Flynn is so busy bringing us up to date or setting up future events that the plot point that does get resolved -- what's really happening at the space station -- seems like an afterthought.

Despite the constant focus on the space program, Lodestar sometimes seems curiously earthbound. Even the book's astronauts-and-asteroid cover has more to do with van Huyten's dreams than events in the story.

Everything that happens is important, though.

Flynn moves his characters around with a series of discoveries and revelations, setting them up so that he can drop a bombshell at the end of the book: van Huyten's worst fears of a massive meteor strike are coming true, and soon.

In many ways, Lodestar is about what Babylon 5 called "the hour of the wolf" -- that time late at night when you're forced to take stock of yourself and your life. If the plot isn't loud and flashy, it's because the characters need enough quiet to hear themselves think.

However, Babylon 5's "Hour of the Wolf" episode had the advantage of being one of many weekly installments. It's more difficult to be patient with a book-length introspective moment, especially when the next exciting chapter is a year away.

If you have that patience, reading Lodestar is like watching a master chess player put his pieces in position. By the final chapter, the battle lines are drawn, the true threat is revealed and the game is ready to move into its next phase.

After such careful preparation, that next round of development should be extremely exciting.