Elena Michaels, a werewolf trying to live a normal life, is summoned home by Jeremy Danvers the pack alpha when they come under attack by an unknown enemy. But returning to Stonehaven means facing Clayton Danvers, the only man Elena has ever loved, and the one who betrayed her by changing her into a werewolf.
Elena tries to keep Clayton at arms length, but he lets her know he'll do whatever it takes to get her back in his life for good. Elena uses the search for the deadly mutt as a distraction from her complicated personal life, but things get worse when a second dead body is found on Stonehaven's property.
Elena and Clayton fall back into old patterns from their former relationship, which causes alarm for Elena who wants to forget the past. Together, they track down the Mutt at a warehouse, but find themselves in a sticky situation when the Mutt shifts to a wolf.
Elena and Clay must put aside their growing sexual frustration as they team up to discover who and why someone has turned serial killers into werewolves.
Elena is overcome by her remembrance of her love affair with Clayton and how he betrayed her trust by changing her into a werewolf to make her his mate, but still defends him from those who accuse him of being behind the murders. Meanwhile, a former Pack member and rival to Clayton returns with information about the Mutt plot.
Daniel Santos is now revealed as the leader of the mutt uprising, and he requests a meet with the Pack to discuss a potential truce. The Pack sees the meet as an opportunity to trap the rebelling Mutts but once again, the mutts are one step ahead of them and some of the Pack end up being hurt.
Elena discovers that Jeremy was stabbed with a poisoned blade. In order to find out the type of poison used, Elena tracks down the girl who stabbed Jeremy. Clayton uses various tactics to try and get Cain to reveal where the Mutts are located. Although unsuccessful, Clayton does get Cain to reveal that Santos has hired Jimmy Koenig to go after the Pack.
Jimmy calls Jeremy for a meeting to end the fight old-school. They fought. Jimmy was about to kill Jeremy but Nick stepped in at time to finish Jimmy off. Elena is attacked by a mutt. Meanwhile, Philip confronts Logan to ask if he was having an affair with Elena, because of the video of the werewolves that was shot at the night they were on a run.
Elena returns to Toronto for her photography show with Clay at her side as protection. She is surprised by Philip, who knows her relationship with Clay is deeper than she's confessed in the past – curious to get to the bottom of it, Philip insists Clay stay with them at the apartment. As the two men sniff each other out, each with their own agenda, Elena tries to prevent her two worlds from colliding. At the art show, Elena is blindsided when Victor Olson, her former child abuser, shows up. Even more terrifying, he's now a Mutt. Philip, already loaded for bear, steps in to protect and defend Elena's honor, taking out all of his frustration and rage on a seemingly helpless Olson. Outside the gallery, Clay confronts Santos, threatening to kill him and end the uprising in its tracks, when a horrified Diane interrupts. Santos manages to escape just as Olson flees the gallery. The evening ends with Philip demanding the truth about Elena and Clay's relationship. When she reveals that they were former lovers and had been engaged, Philip storms out and Elena feels her worlds imploding.
Clay and Elena are at Philip's apartment and while they wait for Jeremy and the rest of the pack to arrive, Clay reveals to Elena that the Mutts are after her. Philip arrives back at his apartment and decides to propose to Elena. Elena rebuffs his proposal and secretly sneaks out to seek counsel from Logan. Logan decides to leave the pack, but after he is attacked by Karl Marsten and Thomas LeBlanc, he asks Rachel to take him back to Stonehaven. Under James Williams' orders, Daniel Santos and Victor Olsen head to Philip's apartment in search of Elena, and in the ensuing fight with Clay and Philip, Elena changes to her wolf form to save Philip. However, Santos and Olsen manage to drug Clay and capture him.
Jeremy and Nick meet up with Elena and convince her to return to Stonehaven to regroup. Meanwhile, Clay is tortured by Daniel Santos and his group of mutts. Santos reveals his original intention was to capture Elena and user her as a pawn to force Jeremy to relinquish his control as Alpha as per James Williams orders. Rachel brings Logan to Stonehaven, where Jeremy helps him to recuperate from his injuries. Meanwhile, Jeremy imprisons Elena to prevent her from meeting up with Santos. When Jeremy leaves to search for Santos, Logan frees Elena and she eventually meets up with Santos to find out what his demands are. Santos reveals his desire to mate with Elena in exchange for Clay's freedom. Elena captures Victor Olsen and convinces him to reveal where the Mutts are hiding Clay, and kills him in the process. Elena frees Clay and together they escape from the Mutts. Jeremy reveals to Elena that Clay bit her in order to save her from being killed by him.
James Williams directs Santos to recruit more mutts to attack StoneHaven. Logan takes Rachel to a motel and leaves her there in hopes of keeping her away from the coming battle but tired of waiting, Rachel leaves the motel and is captured by the Mutts, who use her as a decoy to start the battle to take StoneHaven. Just before the battle, Jeremy tells Nick that he knows where Nick's mother is located. Logan arrives back at StoneHaven to help Jeremy and the rest of the Pack fight the mutts. Elena is captured by LeBlanc, but is saved by Marsten, who has a change of heart. Believing that the mutts have the upper hand in the battle, Williams and Santos enter StoneHaven, but Williams disappears, and Santos winds up being cornered by the Pack. Elena kills Santos. The pack defeats the mutts, but instead of admitting defeat, James Williams confronts Jeremy and reveals his intention to take Elena. In the chaos of the battle, Rachel is kidnapped by James Williams who turns out to be Malcolm Danvers, Jeremy's father. Elena discovers the head of Philip and screams.