Underworld: Endless War is a collection of three short, tie-in stories whose creation was supervised by Len Wiseman, director of the first two Underworld films each tell a different story, and at different periods of history to highlight new events of the Underworld mythology. These stories also tell of what happened before the events in Underworld: Awakening.
These shorts were released in December 20, 2011, as a part of the new Underworld Trilogy: The Essential Collection for Underworld, on Blu-ray. Each episode is a little over five-minutes long.
In 1890, Selene is in Paris, investigating reports of three Lycan brothers, who, as werewolves terrorize the area, but in human form, are posing as lords, and have claimed a castle/mansion as their-own. Selene has been dispatched to investigate the reports, eliminate these self-styled "Lords of the Crescent Wills", and secure the mansion for the Paris branch of the Old World Vampire Coven. From a perch up in the belfry of a high building, Selene sights one of the brothers, Darius, the oldest. She receives a scroll, (via messenger bat), with likenesses of all three brothers and the layout of their mansion, and Selene realizes the reason that Kraven and higher-ups want the castle is to put the balance of power in the area in favor of the Vampires. Determined to exterminate the self-styles Lycan Lords, Selene makes her way after the oldest brother.
Arriving at the mansion first, the oldest Lycan informs his brothers, twins Vregis and Krandrill, that a Death Dealer has found them, and that they must leave at once. But they both do not take this seriously, and, against their brother's warnings, insist that they kill the Death Dealer first. Together, all three brothers try to ambush Selene down in the sewers, thinking that, it being three-against-one, they have her at a disadvantage. Selene, however, proves to be more than they had estimated; she cuts-off half of one of the two younger brothers' ears, and then, with a pair of swords, mortally wounds the oldest brother, who then sacrifices himself to shield his brothers against Selene's gunfire. The younger two brothers flee while Selene finishes-off the oldest Lycan brother. As they leave the estate via rowing boat, they vow revenge against the Death Dealer and the Vampires.
In 1967, nearly 80-years later, Selene has returned to Paris, to investigate familier reports of the two remaining Lycan brothers, who had escaped her decades earlier. Unbeknownst to her, she is spotted in the streets of Paris by the youngest Lycan brother, Krandrill, (from the very same belfrey she had sighted his oldest brother in Part I). While he goes to inform his twin brother, Selene is giving her report to Kraven via telephone. To her disgust, Selene is informed that her presence is 'eagerly-awaited at the mansion' by Lord Clovis. Meanwhile, Krandrill arrives at the backroom of the weed shop they've been working out off. Vregis comments that the 'incense can only hide [them] for so-long', and Krandrill informs him that he has spotted the Death Dealer that killed Darius in Paris. Figuring that she's there as protection for Lord Clovis at the 'Crimson Moon ceremony', being held at their old mansion, they decide to crash the ceremony to lure her out, so that they can both kill her and the other Vampires, and reclaim their old home, all in one night.
Selene drives to the mansion, figuring that 'it's only a matter of time' before the two brothers will attack at the mansion, and she now has their trail. In the middle of the ceremony, the Lycan brothers crash the ceremony and decapitate Lord Clovis, before Selene jumps in after them and opens fire. The brothers retreat to the shadows, circling, before one, (Vregis), dashes out and knocks her against a piller, causing her to drop her guns. Selene recovers, draws her sword, and dashes forward at Vregis, somersaults over his shoulder and drives the blade straight through the back of his skull. With the second brother down, Selene turns her attention towards the third brother, Krandrill, who charges at her, but she responds with her last weapon, a shuriken, severing his left arm clean off. As he flees, Selene comments that it is only a matter of time before he'll 'join [his] brothers in hell'.
In 2012, a few years after the death of Alexander Corvinus, Selene has returned to Paris with the intention of finishing off the last Lycan brother once and for all (Krandrill having deliberately brought attention to himself), and she has brought Michael with her to help. Since Alexander's death, humanity has caught on to the existence of vampires and Lycanthropes, and has begun to identify and exterminate the 'Infected'. As Selene observes, a couple in a car are singled out (by an IPU (Infected Persons Unit) sniper stationed in the same belfry seen in Parts I & II), and tested first with Ag (silver) gas, and then with UV light, revealing them as vampires, and promptly shot. Having been lured back to Paris by Krandrill, Selene and Michael had split up in order to cover more ground; Selene is sent a picture by her contact, a female security guard at the Tati hotel, confirming Krandrill's regular presence there. Selene and Michael talk by smartphone, and Michael recognizes Krandrill in the picture. He approaches the hotel as Selene makes her way to meet up with him there. Krandrill's plan, after having brought himself to Selene's attention again in the first place, is to lure Selene and Michael into an ambush with his harem, where he intends to kill Michael in front of Selene, in retaliation for her slaying his older brothers.
Michael's attempt to take Krandrill by surprise is foiled when Krandrill picks up on Michael's scent first, and Michael hears howling, all before Selene can meet him there, as she has to deal with the IPU men (who also heard the howling). Michael crashes through the entrance, only to be taken by surprise himself by Krandrill (already in werewolf form), and his harem of female Lycans (all of whom are armed), and transforms into his hybrid form. They open fire on him after pinning him to the wall with grappling guns, but Michael breaks free and slashes through Krandrill's harem, before being taken on by Krandrill himself. Krandrill, however, makes the same mistakes as twice-before and underestimates his enemy's strength, and is sent flying out a window. Before he starts to fall, Selene jumps down from off of the rooftop and as she sends him down to street below peppers him with silver bullets. Before he dies, Krandrill gives a passing taunt, that her kind is being hunted now, and that she'll soon join him and his brothers in hell, before Selene finishes him off.
In a voiceover, Selene comments about the 'endless war': "I don't feel 'Victory'; this never ends. (About Kandrill's Last Words) He might be right. We are the Hunted. But as long as I have Him, I'm all right. As long as we're together, I can live forever..."