The drama begins many centuries ago, when the warring forces of ultimate light and darkness, embodied in supernatural beings called "Others," agreed to a truce. Thereafter, both sides policed each other, with the light side forming the Night Watch and the dark side forming the Day Watch. Both sides have agreed that all mortals and future Others cannot be forced to take sides, but must choose the dark or the light.
Naturally, there's a prophecy -- isn't there always? -- that will change everything once fulfilled. Derived from a Byzantine legend about a cursed virgin who started the whole light-versus-dark mess, it states that once the virgin is reincarnated and opens a vortex, it will signal the coming of a Chosen One who can permanently tip the balance of power.
Oh, but there's more. The Others all have various powers -- some are psychic, some shape-shifters, and some vampires, and all have the ability to enter a parallel dimension called the Gloom, which allows them to walk through walls and be invisible.
Cut to present-day Moscow. Our hero, if we can call him that, is Anton (Konstantin Khabensky), a psychic who first discovered his Otherness while trying to make a deal with a dark psychic to arrange a spell on his ex-girlfriend. Twelve years later, he's now a pathetic alcoholic who must drink blood in order to put himself on the same wavelength as the dangerous vampires he's required to keep tabs on.
While on a mission to protect a child from the telepathic come-ons of a hungry vampire couple, Anton discovers that the vortex is arriving, and it centers on a terminally unlucky doctor who is probably the reincarnation of the cursed virgin.
If there's a weakness to all this, it's that there are just too many supernatural beings with too many powers to get a handle on. And this is just part one of a trilogy. While all may not be clear yet, there's plenty here to make you curious about the rest.