The book is set in Borogravia, a country that is in dire straits because the populace worships a dead god called Nuggan, who decreed (among other things) that crop rotation, women wearing men's clothes and doing men's work, ears, the colour blue, chocolate, sneezing and babies are all Abominations. By attempting to do nothing Abominable, the Borogravians have reduced themselves to a starving, bellicose nation. Borogravia is supposedly ruled by a Duchess, who is also worshipped (seeing as how Nuggan is presently regarded as insane by most of the population), but no one has seen her for decades.  In the midst of a war started by a Borogravian assault on the Ankh-Morpork clacks (it was an Abomination unto Nuggan), Polly Perks decides to go into the army in an effort to find her brother Paul, who is missing in action. She runs away, gives herself a boyish haircut (although she is not quite able to part with the hair she has cut, which she considered her one beauty, and packs it in her bag), and enlists in another town under the assumed name of Oliver Perks ("Oliver" from the folk song "Sweet Polly Oliver"). Among the other recruits for the Tenth Regiment are an Igor, a troll, and a vampire, who no longer requires blood - as a reformed vampire, his addiction has been transferred to coffee instead.  Fortunately for Polly and the other recruits, they have been recruited by and come under the protective wing of a legendary Borogravian sergeant named Jackrum. Jackrum is famed within the Borogravian army, feared by its enemies, and soon shows himself to be competent, decent, and resourceful. He also appears to have an inordinate amount of influence with the Army's High Command, which is best illustrated by the fact that a retirement age has been attempted to be enforced on Jackrum several times, and each time Jackrum has used his contacts to fudge the dates of his birth/enlistment in order to be under the limits, or orders have come from High Command to countermand the attempt to retire Jackrum. Jackrum is also capable of being quite ruthless, especially when it is in the name of protecting his "little lads".  On the recruits' way to get weapons, uniforms, supplies, and training, Polly, now known as "Ozzer", has an opportunity to look at the other recruits. Almost immediately she discovers that there is another woman in the regiment: Lofty, who has apparently joined to be with her boyfriend, Tonker. She also confronts Corporal Strappi, the regiment's bully and a "political" (a soldier who spies on other soldiers and reports any technical violations of obscure regulations) who later deserts when word comes that they will be sent into action.  The night Strappi deserts, Polly discovers that Shufti, another private, is also a woman in disguise. She has joined to go looking for the father of her unborn and illegitimate child. When she realizes this, Maladict, the vampire, calls her aside and tells her that he, too, has been noticing that there are many girls in disguise.  An enemy cavalry detachment, alerted to the regiment's presence by Strappi, comes looking for the young recruits. Two of them harass Polly, who has found a dress and convinced them that she is a barmaid. She knocks them out. The remaining cavalry attack the other members of the regiment, who easily overcome them and take them prisoner. While Igor is patching up one of the prisoners, Sargeant Jackrum interrogates the leader. They are interrupted by an impressed reporter from Ankh-Morpork, William de Worde. During the commotion, Strappi sneaks back and steals Maladict's coffee and the shorn locks of Polly's hair.  Maladict tells Polly that Tonker is actually yet another woman, and distracts Polly from her initial confusion by pointing out that she (though apparently male) is wearing a dress. Polly gets slightly fed up with his patronizing attitude, and snaps at him. Polly sees that Private "Wazzer" Goom, an extremely religious "boy", curtsies instead of bows to "his" portrait of the Duchess. The morning after the run-in with the cavalry, Shufti brings up the fact that most of the privates are, in fact, women. Polly and Jade (the troll, who previously went by the name Carborundrum) own up to their femininity. Maladict, though asked, merely gives a cryptic smile and refrains from admitting whether he is male or female.  That night, they stay at a house whose owners were killed by Borogravian deserters. This leads to a general sense of disquiet and a growing suspicion in Polly's mind that Borogravia is actually losing the war. Maladict discovers his coffee beans are missing and is extremely distraught because he, being a "reformed" vampire, has transferred his longing for blood to a craving for coffee. The members of the regiment also start to get to know each other. Lofty, Tonker, and Wazzer all come from Polly's town, where they were abused by their caretakers and employers. As they leave the campground, Lofty sets the house on fire.  On their way to join the remains of the army, they encounter and capture an enemy mobile clacks unit (a directional torch-light with a shuttered opening, used to transmit morse code at night). Later, they again run into William de Worde, who tells them that they are losing the war, that they will be slaughtered if they go to the front, and that they should stop being so stubborn. Lt. Blouse uses this opportunity to suggest that the squad intends to rally a force of deserters and unit remnants in the mountains, which prevents the enemy from invading Borogravia, as they fear a flanking attack (or counter-invasion) by the non-existent force. Using the captured mobile clacks and the accompanying codebook to pretend to be the original operators, they send a signal claiming that there is a massive force of Borogravian irregulars camped in the mountains, further enhancing the deception.  After arriving in the valley where the main army is camped, the squad is able to see the utter futility of joining up with the main force: the massive Borogravian command fortress known as "The Keep" has been taken in a sneak attack, and the Borogravian army is laying a futile siege to recapture it.  The squad comes up with a plan to retake a fortress: they will enter the fortress by dressing as washerwomen and release the prisoners held there. Although this plan is rather clichéd and stupid, even by Borogravian standards, the women know that they have another advantage: who would expect a woman to dress up as a man to dress up as a woman? The resultant mental confusion would obviously turn any guard's brain.  Unfortunately, Blouse airily informs his 'men' that they are incapable of acting like women--being too masculine--and so he will be the one to go, as he often played women in school-theatre. Jackrum, who has developed a dislike for the officer, agrees and says that he will stay with his "little lads." Maladict's inability to access coffee has reached the point where he is reverting to vampirism, having passed through the delusions and "flashsides" to the Vietnam War he was having before, which included chalking "Born to Kill" on his shako, chainsmoking, and insisting that the group was being tracked by Charlie. Polly describes his eyes glowing red, and his fangs lengthening. Just as Maladict is about to pounce on Polly and attack, a sack of coffee beans falls out of the sky. The squad asks Wazzer if the Duchess had been the one to supply it. In fact, it was a gift of the airborne unit of the Ankh-Morpork city-watch (a gnome on a buzzard), who has been following the squad for some time. The watch commander (and current ally of Borogravia's enemies), Sam Vimes, is planning for a quick end to the war without too much bloodshed, so that humanitarian aid can reach Borogravia before food runs out in the winter. The squad is part of this plan, as explained later.  Jackrum takes them to the Borogravian camp, where they tell him that they must also try their hand at getting into the castle disguised as washerwomen. He relents and lets them all go (except for Jade the troll and Maladict, who is still recovering from his lack of coffee). They find dresses and attempt to get in, but are stopped by the guards. Shufti lifts her skirt and Tonker throws a temper tantrum in order to prove their identity as females, and they find Blouse ("Daphne"), who is still convinced they are all actually men. He is the only one of the group who did not have to partially undress or throw a tantrum to convince the guards that he was female, thanks to his disturbingly realistic act, which he sometimes appears to take a little too seriously.  They leave the wash and go in search of the dungeons. As they pass through the crypts they are confronted with a bunch of zombies. The Duchess possesses Wazzer and convinces the Borogravian military dead to leave them alone. As they leave the crypt, they are identified as soldiers, recaptured and locked in a kitchen. Lofty uses an improvised flour dust bomb to blow the door off their cell, and they release the prisoners.  The released prisoners praise the monstrous regiment's deeds until it is discovered that the men who disguised themselves as women really are women (Although Blouse takes it fairly well when everything is fully revealed, stating that he would not trade the women for any men he was offered). This horrid infraction of the Abominations is brought to the attention of several officers of the Borogravian Army. Strappi, who has reappeared as a Captain, testifies against them, (with Polly's hair as one part of the evidence), but Jackrum (who has led an external attack on the keep once the main gate was opened from within) clears the matter up when he points out that many important generals of the Army are also women (After clearing the room of all actual men). Faced with this and the Duchess's spirit showing itself through Wazzer, the generals let the girls go.  Later, Maladict confesses that she is actually Maladicta. She expected Polly to be shocked and make a big deal out of the whole thing. But Polly, whose mind had been elsewhere, simply dismissed the whole thing, saying that it didn't truly matter.  Commander Sam Vimes meets with Polly and Maladicta and reunites Polly with her brother. He explains his plan to the girls, and congratulates them on a job well done. When asked why he would support the independence of Borogravia, Vimes explains that his country does not want Borogravia's main enemy to become a large, powerful country that could endanger Ankh-Morpork's interests. He suggests that his country is willing to prop up Borogravia provided the more absurd aspects of Nugganite culture are removed (so that the country can actually function).  Wazzer, no longer the Duchess, leads the Borogravian army in an assault on their own capital in order to gain entery to the duchess's home. This part of the book is not actually narrated, only described by Polly afterwards.  Before this assault, Polly confronts Jackrum, who admits that she is also a woman who ran off to be with her man; he died shortly afterwards, and then Jackrum had a son and left the child to be adopted. Polly tells her that she should go and find her son and pretend to be his father (Jackrum thinks he'd dislike the reality--that the obscene, obese sergeant is actually his mother), and she does.  That winter, the country manages to struggle through without too much starvation. Lofty and Tonker burn down their old school and steal a great deal of money, Shufti moves into Polly's old inn, and Wazzer becomes a cared-for member of the royal family's household. That summer, as Borogravia once again gets into a dispute with the same country as before, Polly rejoins the army.  Polly had been promoted to the rank of sergeant before she had left the army. She suspected Jackrum had something to do with it. She had expected to go alone, but as she was about to leave Maladicta turned up again, in uniform. They both rejoin the army together, this time openly as women, in an attempt to at least reduce the effect of stupid decisions made by high-command.

A really simple and yet complex book, it's all about women fighting in war, but (sometimes) badly disguising themselves as blokes because they have a really weird god and en even weirder religion to enforce the weirdness (although they're not as weird as the 'Christian' Right). The rest of the book is a (largely off page) attempt by Vimes and the watch to try and find a quick end to the war. The main characters are all pretty well rounded (and not in the place where it'd show the most) Polly/Ozzer is the most rounded of all as much of the book is told from her pov. The nature of the conflicts also echoes the numerous wars in what was once Yugoslavia with nation trying to kill nation over some matter or other. The light clacks are an interesting development too and show an increaded symbolism of the accelerating techology on the Discworld. In The Colour of Magic we're definitly in a dark ages type culture, lots of heroes and wizzards and high adventure, then the books quickly advance through the medieval stage by the time of Guards! Guards! and then the Rennaisance by the time of Men at Arms, now we're in a sort of industrial revolution with the advent of the clacks and newspapers and a more modern approach to warfare.