waterlilybarb

Episode 1: Omega
When Lydia goes missing from the hospital, werewolves and hunters alike begin a search to discover not only where she is, but what she's become.

Episode 2: Shape Shifted
The night before the new full moon, Isaac's father is murdered. When he's taken into custody, Scott, Stiles and Derek resolve to break him out before the Argents get to him first -- and before the newly bitten teen turns into a werewolf.

Episode 3: Ice Pick
Scott struggles to stop Derek from creating new werewolves, while Argent decides to officially begin Allison's training and the new creature in town takes another victim.

Episode 4: Abomination
When the new shapeshifter strikes again, Scott has to recruit a reluctant Allison to acquire a rare book in Gerard's collection, while also once again surviving dinner with her family.

Episode 5: Venomous
Derek becomes convinced that Lydia is the shapeshifter they're after, forcing Scott to gather his friends -- and even some enemies -- to protect her.

Episode 6: Frenemy
With startling new information about the shapeshifter, Scott and Stiles hurry to protect their friends while Allison is given an investigative task by her family.

Episode 7: Restraint
As Lydia begins to make connections about the bite from Peter, Jackson causes new problems for Scott and Stiles. Meanwhile, Derek has a crisis of faith in his leadership as a new Alpha.

Episode 8: Raving
During a secret concert, Scott and Stiles come up with a method to trap the new shapeshifter. At the same time, Allison's mother devises a plan of her own to take care of Scott once and for all.

Episode 9: Party Guessed
Even as his relationship with Allison becomes further strained, Scott and Stiles must attend Lydia's birthday party while Derek locks his new wolves up to watch after them on their first full moon together.

Episode 10: Fury
With a shocking secret revealed, Scott, Stiles, Melissa and Stilinski are taken hostage in the Sheriff's Station. Things get completely out of hand when Allison tracks Derek to the station, bringing Argent and Gerard with her.

Episode 11: Battlefield
Scott must help win the championship lacrosse game while also trying to figure out how to stop Gerard. At the same time, Allison and Argent continue their hunt of Derek and his wolves.

Episode 12: Master Plan
With a shocking death on the lacrosse field, Scott and his friends rush to figure out Gerard's master plan while Derek plots to take him down using his own methods.

Source
contributed by codebreaker

waterlilybarb

Episode 1: Tattoo
Derek and Isaac search for Erica and Boyd in the Season 3 premiere.

Episode 2: Chaos Rising
Stiles' friend goes missing; Allison and Lydia search for Boyd and Erica.

Episode 3: Fireflies
Scott and Derek seek help from an unlikely ally.

Episode 4: Unleashed
Scott tries to prevent a deadly confrontation; Stiles defends the werewolves.

Episode 5: Frayed
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.

Episode 6: Motel California
Scott and the gang undergo strange experiences when they are stranded at a motel, causing them to believe members of their own group may be the mysterious killer's newest targets.

Episode 7: Currents
Scott's trusted mentor and boss is threatened; Deaton, Kali and the Twins go after Derek.

Episode 8: Visionary
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.

Episode 9: The Girl Who Knew Too Much
Allison becomes suspicious of someone close to her.

Episode 10: The Overlooked
Scott and Derek get trapped inside an evacuated hospital during a powerful storm.

Episode 11: Alpha Pact
Derek and Peter try to save Cora's life.

Episode 12: Lunar Ellipse
Scott performs a dangerous ritual in an attempt to stop Deucalion.

Episode 13: Anchors
Strange side effects plague Scott, Stiles and Allison.

Episode 14: More Bad Than Good
An unlikely ally offers to help Derek and Peter.

Episode 15: Galvanize
When a convicted serial killer escapes during surgery, Scott and his friends assist the person the killer is targeting.

Episode 16: Illuminated
Beacon Hills is under curfew from the power outage; the teens throw a blacklight Halloween party; Scott tries to earn Kira's trust.

Episode 17: Silverfinger
Scott's friends protect him from a hostile enemy.

Episode 18: Riddled
Stiles goes missing; Lydia tries to master her new abilities.

Episode 19: Letharia Vulpina
Lydia and Allison seek out a unlikely teacher. Scott has to prevent a disaster.

Episode 20: Echo House
Stiles has to make an important decision over Eichen house. Scott and his friends seek out an important Japanese artifact.

Episode 21: The Fox and the Wolf
Kira realizes her unusual abilities.

Episode 22: De-Void
Scott and Lydia join forces. Meanwhile, Stilinski faces a review board.

Episode 23: Insatiable
Kira faces an unexpected enemy.

Episode 24: The Divine Move
One last stand is made by Scott, Derek and their allies in the Season 3 finale.

Source
contributed by codebreaker