The American edition of the book consists of three novella length stories. The European edition only contains the first two of the following three.
(this story is being told from the point of view of Alisa Donnikova)
Alisa Donnikova, a young but powerful Dark Other, leaves her house to attend a meeting with her comrades in the Day Watch. The team is on a mission to apprehend and recruit an uninitiated Other, a practicing Dark witch who has so far eluded the bureaus responsible for finding and initiating unlicensed practitioners of magic. It seems a routine operation. But when they arrive, the Night Watch team has already made the arrest. A fierce battle ensues, during which Alisa almost dies. Drained of her powers, she is sent to recuperate at a youth camp near the Black Sea. There she meets Igor. The chemistry between them is instant and irresistible, and Alisa finds herself falling in love. But then comes a shattering revelation: Igor is a Light Magician. Alisa remembers him as one of those involved in the battle that left her crippled. Had they known what they were, they would have not entered their relationship. But now that they know, Igor (who reacts with rage, feeling he was tricked) challenges Alisa (who reacts with a more depressed note of sadness) to a duel. Alisa allows Igor to choose the site of the battle: off-shore (while the two are swimming). Alisa chooses not to fight back, allowing Igor to magically pull her under the water and drown her while she contemplates the fact that as a Dark Other, she could gain no power from the humans happily frolicking on the shore even if she tried. While this is going on, Makar, a boy that had become infatuated with Alisa, swims out to rescue her and also drowns.
Note: The first scene of this novella forms the basis for the first scene of the film Night Watch. In the book, a woman named Natasha goes to a witch to have her cast a spell to make her husband fall back in love with her. In the movie, Anton goes to the same witch to have her kill what he thinks is his wife's child with her adulterous lover (it turns out to actually be his own child). Both scenes play out in much the same way from there, but the arrival of the Day Watch and subsequent battle does not occur in the movie.
(this story is being told from the point of view of Vitaliy Ragoza)
A man named Vitaliy Ragoza awakens while walking through a park late at night with no memory of his past or who he is. Following an internal instinct, he is able to protect himself from a werewolf and board a train to Moscow. Once in Moscow, still following instinct, he registers his presence as a Dark Other with the Night Watch and proceeds to stumble into a series of seemingly accidental encounters with the Night Watch, often resulting in a Night Watch member dying. He kills Tiger Cub in self-defense as she seeks revenge for him setting a trap that (legally) kills a Night Watch investigator trespassing in his hotel room.
While this is taking place, a Day Watch splinter group named the "Regin Brothers" stages an attack on the Inquisition to steal a powerful artifact named "Fafnir's Claw". Only 4 Regin Brothers survive and they head to Moscow. Ragoza inadvertently winds up in possession of the claw, but does little with it and gives it back. Eventually, the Inquisition calls a meeting to determine what is going on and whom, if anyone, should be held responsible. Anton is called to attend, but Zabulon encourages him not to with the promise that he will be able to live freely with Svetlana if he does not.
After Vitaliy and Anton have a car accident (deliberately staged by Anton) on the way to the meeting, Svetlana concludes that Anton and Vitaliy are engaged in a duel that will result in Anton's death. When Vitaliy arrives at the meeting alone, she assumes the worst and strikes him with all of her considerable power, leaving her dangerously drained (like Alisa above). Vitaliy is unaffected, although his clothes and MiniDisc player are destroyed. Anton then appears and gives Vitaliy his own MiniDisc player as a replacement. The Inquisition concludes that Vitaliy is a manifestation of the Twilight attempting to rebalance Light and Dark since light has become overly dominant and is in danger of being able to recreate the world as a paradise. Vitaliy was able to neutralize Svetlana by his presence and restore the balance. Svetlana is sufficiently reduced in power that she and Anton are now theoretically able to live as equals, as Zabulon promised. Vitaliy leaves the courthouse, listening to music, and dissipates into the Twilight, his purpose fulfilled.
(this story is the only story in the tetralogy without any narrator)
The third story revolves around a trial by the Inquisition to investigate the events of the first two stories. The first part of the story deals with various involved parties travelling to Prague (where the trial will be held), the second part involves the characters meeting in a number of different configurations and talking, the third part involves the trial itself.
All of the surviving major characters of the first two stories are on their way to Prague, which is the new location of the Inquisition after the Regin Brothers destroyed the old one. Edgar, a medium high level operative, is going to plead the Day Watch's case. Edgar assures the 4 remaining Regin Brothers that the Day Watch will protect them. Anton is going as a prosecutor for the Night Watch. Igor is already there being put up (but not held in custody) by the Inquisition. In Prague, Anton meets an American Air Force pilot who is also a Light Mage. The pilot is proud of his work (bombing Kosovo). Anton is appalled that anyone can perform such evil acts and still align themselves with good. Anton and Edgar meet over beer and discuss dark vs. light philosophy. Edgar is clearly not a terribly enthusiastic Dark Other, but he's doing his job nevertheless. Anton then goes to visit Igor while Edgar, left to his own devices, uncovers a lot of evidence to indicate that Zabulon is setting him up to be killed in order to facilitate the resurrection of Fafnir. He's understandably frightened and angered. Meanwhile, Anton, eager to distract the suicidal Igor, gets him roaring drunk on Vodka and attempts to draw him into a strategy session to try and figure out what the Day watch is up to, with some success. They wonder whose destiny it was that Olga changed at the end of Night Watch and here it is revealed that, though Svetlana's child would always have been a powerful light Other, the changes mean that her birth has been timed to make her a Light Messiah. Gessar arrives and pleads with Igor to stick around for at least another 20 years. Igor is non-committal.
The next day, the trial begins. The Regin Brothers are tried first and are found guilty only of lesser crimes, though they transported Fafnir's Claw, they didn't participate in the theft. They are stripped of all but the very smallest of their magical powers and sent on their way. The main focus of the trial is the events of the first story. A number of minor charges against Gesar and Zabulon are dismissed under technicalities. In order to get to the bottom of the case, they temporarily resurrect Alisa, who implicates Zabulon in her demise, stating that Igor was not responsible for her death. Igor is cleared of all charges. However, when Alisa is sent back to the Twilight, Igor follows her, dying himself. Zabulon is ecstatic, admitting that he had indeed planned to sacrifice Alisa in order to remove Igor, saying that Igor was the only one that could have trained the upcoming Light Messiah.