Underworld: Blood Wars

The war between the Vampires and the Lycans wages on with the Lycans led by Marius are close to defeating the Vampires. He thinks if he can get the hybrid daughter of Vampire Death Dealer Selene, her blood will be the key to defeating the Vampires once and for all. But when they attempt to capture her, they fail and she tells one of them to tell Marius, she doesn't know where her daughter is; her daughter has cut ties with her. At the same time, Semira, Vampire Elder implores Thomas, another elder and father of David, Selene's ally to convince the Council of Elders to give Selene whom they deem a traitor, amnesty so that she could train new Death Dealers to deal with the Lycans. They grant it and send word to Selene who comes and trains the aspiring Death Dealers. It's when she battles one of Semira's people, that he subdues her with a toxin that paralyzes her. Semira then has her man kill the trainees with Selene's weapon. She then reveals she wants Selene for her blood. Eventually David learns of what Semira is doing and tries to get Selene away and takes her way to the only other Vampire stronghold there is. Eventually Marius learns of this and sets out to find Selene and find out for sure if she knows where her daughter is. And it's while they are there at the stronghold that David learns the truth about his lineage.