In his new role as Imperial Auditor, Miles Vorkosigan finds himself on Komarr, a planet where his father has an unfortunate reputation, being blamed for a massacre of government officials who had surrendered to him during the planet's conquest. He is there, along with Professor Vorthys, an older, more experienced Auditor and engineer, to investigate whether the destruction of a solar power satellite vital to the ongoing terraforming of the planet was an accident or sabotage. Miles uncovers an extremely dangerous Komarran conspiracy, one which threatens the entire Barrayaran Empire, and is attracted to Vorthys's niece, Ekaterin Vorsoisson, the unhappy wife of an Etienne "Tien" Vorsoisson, the head of one of the terraforming facilities. Tien suffers from a degenerative genetic condition, which would stigmatize him with other Barrayarans, and has tried to raise money for secret treatment by gambling on the Komarran financial markets. Heavily in debt, he has been bribed by his subordinates to ignore certain irregularities, which he believes are just a swindle, but are actually part of their plot against Barrayar. Tien Vorsoisson dies accidentally, partly due to his own carelessness, after the conspirators capture him and Miles. They are left shackled and exposed to the Komarran atmosphere with only their breathing masks to sustain them, but Tien has neglected to recharge his mask's reserve. Ekaterin finds her husband dead and Miles injured from his efforts to escape. She had been about to leave the marriage, having discovered Tien's gambling losses, but received a mysterious call to pick up Miles and Tien at the remote facility. Miles starts an in-depth investigation of the terraforming facility and its staff, using Barrayar's Imperial Security officers stationed on Komarr. Having been partly responsible for Tien's death, he tries to repay the blood debt by securing treatment for Ekaterin's young son, Nikolai, who inherited the condition. He and Vorthys recruit Komarran physicists to examine the advanced equipment the plotters seem to have purchased, and determine what they intended to do with it. In traditional Barrayaran mourning, Ekaterin leaves Komarr to travel to one of the orbiting stations where she will meet Vorthys's wife, the "Professora", who is a brilliant academic in her own right and Ekaterin's favorite relative. She and Ekaterin accidentally encounter one of the conspirators who have gone to the station to complete their plot. They are taken prisoner. Their captors explain that they are not terrorists, but have a way to cut off Barrayar from the rest of the settled systems. They do not know that their early experiments were the cause of the destruction of the solar satellite. Miles, having guessed the nature of the plot, realizes the station is in peril and hurries there to stop the plotters and save Ekaterin and the Professora. By the time he arrives, Barrayaran Security has the plotters under siege with Ekaterin and the Professora as hostages. After calming the situation and persuading the plotters to surrender to him, he is surprised and utterly delighted to discover that Ekaterin has a previously hidden talent for inflicting mayhem on her enemies and has already dealt the plot a fatal blow. In the coda Miles bids farewell to the two women before returning to Barrayar to report to Emperor Gregor. His slightly odd behavior does not go unnoticed and he and Ekaterin, bantering about his previous relationships with women, catch each other off-guard. Each is left with questions about the other. Their relationship develops in the next novel, A Civil Campaign. In a departure from the style of previous Vorkosigan books, the point of view is split between Miles and Ekaterin, offering an outside view on Miles.
Reception
Komarr has had a positive reception from reviewers. Writing for Tor.com, Jo Walton stated that "The plot of Komarr is one of the best and tightest in the series...it’s a perfect mystery, with all the clues in plain sight for a re-read but cleverly misdirected. It also has plausible villains who think of themselves as heroes", and Nicki Gerlach stated in her review for The SF Site that "if this book is any indication of what's to come, it's a chapter in which I'll be very interested indeed."