Derek and Isaac search for Erica and Boyd, and a new wolf pack arrives in town with its own menacing Alpha.
Allison and Lydia stumble upon a possible clue to finding Boyd and Erica while a childhood friend of Stiles goes missing.
With Boyd and Cora on the loose and under the influence of the full moon, Scott and Derek must turn to an unlikely ally for help.
While Scott tries to keep Isaac from engaging in a deadly confrontation with the Twins in school, Stiles attempts to prove his theory that the killings have nothing to do with werewolves.
During a bus ride to a cross country meet, Scott and his friends flash back to the events of a preemptive strike against the Alphas that has left several injured and possibly one or more dead.
Stranded at a motel for the night because of the postponed cross country meet, Scott and the others suffer strange experiences that cause them to believe members of their own group may the mysterious killer's newest targets.
As the danger begins to reach closer to Scott, threatening his trusted mentor and boss, Deaton, Kali and the Twins go after Derek.
Seeking answers, Scott, Allison and Stiles hear stories told by two unlikely narrators and discover a secret about the color of a werewolf's eyes.
As Allison begins to suspect someone dangerously close to her may be involved in the murders, Scott and Stiles conclude that Lydia's rising talents may be their best bet to solving the murders.
Trapped inside an evacuated Beacon Hills hospital by a powerful storm, Scott and Derek must defend themselves against the Alphas while trying to figure out how to save Cora's life.
With the threat growing far more personal and time running out on innocent lives, Scott is forced to make a difficult choice in order to save both friends and family. Derek and Peter try to figure out how to save Cora's life.
Under Deaton's advice, Scott and his friends use an ancient but extremely dangerous ritual to help them both save the lives of the people they love and stop Deucalion from achieving his sinister goal.
Three weeks after saving the lives of their parents, Scott, Stiles and Allison begin to suffer strange side effects from their ritual sacrifice. At the same time, the newly enlightened Sheriff Stilinski scours through old cases.
Scott and his friends race to figure out how to catch the Werecoyote before it's hunted down while Derek and Peter are broken out of captivity by an unlikely ally.
On the night before Halloween, Mischief Night, a convicted murderer brought to Beacon Hills Hospital for surgery escapes, forcing Scott and his friends to step in to help when his unexpected target becomes clear.
With Beacon Hills under curfew due to the power outage, the teens decide to throw a black light Halloween party while Scott tries to get Kira to trust him in the midst of an attack by a strange new threat.
Scott's friends pledge to protect him against him against an increasingly hostile enemy while Argent, Isaac and Allison search for answers through an old adversary from the Japanese Yakuza.
When Stiles goes missing in the middle of the night, Scott and the others embark on a desperate search while Lydia tries to master her new abilities.
Signs of sabotage appearing all around them, Scott and his allies desperately try to figure out how to prevent disaster as Lydia and Allison seek an unlikely teacher to focus her power.
Scott and his friends seek an important Japanese artifact while a mental health institution called Eichen House offers both answers and a difficult choice for Stiles.
An important clue to defeating their enemy is revealed through the story of a World War II Japanese-American Internment camp while Kira's role becomes ever more crucial as she begins to realize her own unusual abilities.
With Deaton and Peter's help, Scott and Lydia combine their abilities in a desperate attempt to gain the upper hand. At the same time, Stilinski faces a review board that may decide his future.
Kira finds herself facing an unexpected antagonist while Scott and his friends try to survive against an enemy growing ever stronger.
Struck by disaster and nearly defeated, Scott and Derek call on their friends and allies to make one last stand.
