This is an omnibus edition of Bujold's 3 earlier novellas, framed by Illyan's interrogation of Miles into the enormous bills the Dendarii Mercenaries seem to accumulate under his command. The framing story is set shortly after Brothers in Arms.
Mountains of Mourning (5++++++ stars) - set after Miles's graduation from the Imperial Service Academy, just before The Vor Game
already reviewed here - still dearly loved.
Labyrinth (3 stars) - set after Cetaganda/Ethan of Athos
Miles is sent to Jackson's Whole to extract a geneticist - whose terms are that Miles has to kill the last remnant of an experiment into creating super-soldiers, animal genes mixed with human DNA. But Miles doesn't find a monster, but a frightened, disillusioned girl.
The weakest of the 3 stories. Not because of the message, but it seems very compressed. Jackson's Whole and Taura would have deserved a longer introduction, especially because both will turn out to be quite important to Miles's growth as commander and human-being. The way the story stands now, Taura latches on too quickly... I don't know... one tumble in the sheets (well, a stone-cold floor) and she's convinced Miles takes her as fully human? And Miles thinks that the body can't lie? I mean, I'm happy Miles thinks for himself (sometimes too much) and doesn't simply follow orders stupidly - and Taura is certainly worth saving... but... still not satisfied with this story.
Borders of Infinity (4 stars) - set right before Brothers in Arms
Miles is sent to infiltrate a Cetagandan prison camp. Initially set to rescue one person he ends up organizing the whole camp.
Again a story that could profit from expansion because again Miles convinced those disillusioned prisoners who are merely existing instead of living, entirely without hope, that there's someting worth living for, a future worth fighting for. Bujold doesn't pull any punches describing the situation there. The Cetagandans are complying with the interplanetary charta to treat PoW... but only literally, reality is quite another thing entirely. You actually feel hope and even sanity leak from you while reading this story. In the end even escape isn't a victory to celebrate.
Curiously, this prison escape also marks the beginning of the end of Admiral Naismith - even if Miles only later learns that fact years later (in A Civil Campaign).
Overall, 3 stories definitely not to be missed in this saga.