Bujold's first novel featuring an adult Miles Vorkosigan — the birth-defect stricken scion of Count Aral Vorkosigan and Cordelia Naismith — is a rousing space opera adventure that, while it lacks the polish of the series' later volumes, provides entertainment in spades. The story begins as Miles, at 17, fails to qualify for his officer's candidacy in the Barrayaran Imperial Military Service due to his brittle bones and stunted growth. Miles' father, to assuage the young man's humiliation and feelings of failure (in Barrayar's miliaristic culture, such humiliation is strong), suggests Miles take an extended vacation on his mother's homeworld of Beta Colony. And that's just what Miles does, with his loyal retainer Bothari, and Bothari's adopted daughter Elena, in tow.
But Miles isn't content to sit idly by. Determined to prove himself (to himself, as well as to his father), Miles launches a hare-brained scheme that involves purchasing a ship with credit he doesn't have and going into business for himself in shipping. Or rather, smuggling. The first commission Miles takes involves supplying one side of a fierce war brewing on the remote colony world of Tau Verde IV. With a skeleton crew consisting of his companions and a handful of hired dregs and malcontents — one of whom is even a deserter from the Barrayaran military — Miles very quickly finds himself in over his head. Forced by circumstance to become a bullshit artist par excellence, Miles concocts an imaginary mercenary force, the Dendarii Free Mercenaries, of which he is the leader, and before long finds himself a major player in a planetary conflict. With everything he is doing built upon a house of cards, how long will it be before the whole thing comes tumbling down? And can he even keep that from happening?
The first half of The Warrior's Apprentice — in which Miles' wild scheme takes shape — occasionally threatens to go over the top into the realm of the too-far fetched. But Bujold keeps a handle on the whole thing through a ready wit that already demonstrates much sophistication, though this is only her second published novel. And though this book doesn't yet display the maturity of, say, Barrayar, published five years later, what is most impressive is the consistency with which Bujold has already imagined her saga's course of events. This novel references events in Barrayar (which, truth to tell, was outlined at the time Bujold wrote Shards of Honor) with such fidelity to series continuity that if you choose to read the Vorkosigan series in chronological order, rather than in publication order, you'll scarcely notice the seams.
The second half of the novel is the better half, as Miles realizes that the lie he has so carefully constructed has evolved into a new truth, one with real consequences, in which honor and lives are at serious stake. Facing those consequences will involve a great deal of personal growth under the kind of pressure that has broken better men. Bujold isn't afraid to hurt her characters (or you) where it counts, and she avoids the easy reliance on hackneyed convention that would cause her book to be lost in the shuffle of all the other forgotten, formula space epics SF has chewed up and spit out over the decades. There's a substance here in this early novel that marks Bujold as an emerging, important novelist.
If you love solid space opera rooted in strong character, you can't go wrong with the Vorkosigan saga. The Warrior's Apprentice already displays the craft and the heart which would soon make Lois McMaster Bujold one of the most feted talents in SF. Followed — in the series' continuity, not in publication order — by the novella "The Mountains of Mourning" in the collection Borders of Infinity, and Bujold's first Hugo winner, The Vor Game.