He asks Scott to hit the button for the second floor which Scott complies. Afterwards, he asks the young man if he wouldn't mind helping him around as a guide for a while. Scott reluctantly complies with the man placing his hand over the teenage beta.
The lead alpha observes his prey with a dangerous smile. He serenely walks over and kneels before the woman. He touches Braeden's face; he compliments her beauty, though he acknowledges her bravery. A bleeding, unflappable Braeden talks back at the depraved werewolf, saying she knows his fear of Scott's potential.
Deucalion: "I'm aware of a certain potential threat. But then someone once taught me a very smart way to eliminate a threat: "Get someone else to do it for you.""
The Alpha Pack is stationed in the Beacon Hills First National Bank to spring the trap for Derek Hale anticipating he'd rescue his betas. Once Derek and Scott breach the bank's vault's wall, and the full moon-induced-homicidal Vernon Boyd and Cora Hale savage them, Deucalion has Marin Morrell seal the mountain ash barrier on the perimeter of the vault.
Deucalion: "Don't kid yourself, Marin. It's not the first time you've gotten your hands dirty."
The head alpha then takes his emissary's arm as she escorts him out of the bank.
Deucalion: "Everybody done? 'Cause just listening to that was exhausting. So ... let's chat."
Derek gasping in pain, demands Cora be let go. Deucalion motions at Ennis as a gesture of good will. Deucalion scolds Derek for insinuating he's there to kill him, lecturing the younger alpha that he has far more "vision", even for a blind man, making conversation. After Kali suggests that he speed things along, just in case Derek were to die, Deucalion outlines the hazard with being in a pack of only alphas: "Everybody wants to make the decisions."
Deucalion: "Do that and I won't have to ask you to kill the others ... you'll do it on your own.
The sociopathic Deucalion gives a speech explaining the Alpha Pack's rule of entry. He bring up the everyday rule that a pack is only as strong as its members, unfolding and flexing out his four-section cane. He recalls a time that after he lost his eyes, a beta of his tried to usurp his position as alpha, assumed he was unfit to be the alpha anymore and so Deucalion killed him, folding one section of his cane.
Deucalion: "I took the individual parts and became a greater individual whole."
Deucalion then touches and examines Derek's face. He remarks his resemblance to his mother, then tells Derek they'll get to know each other as he did with her.
Deucalion: "Know me? You've never seen anything like me. I am the alpha of alphas. I am the apex of apex predators. I am DEATH, DESTROYER OF WORLDS. I - AM - THE DEMON WOLF."
His roar has shattered the lenses of his glasses, remarking he hates when that happens. Having handed their proposition, Derek is freed, and Deucalion and his subordinates walk with confidence out of the loft, with Kali guiding Deucalion.
The alphas' leader silently walks up to them. The Merged werewolf is immediately submissive. He dissolves, separating back into the individual twins. Deucalion sharply slashes their faces with the concealed dagger in his cane for their breaking rank. They follow him out of the high school.
Deucalion: "Come on, Scott. Put those away. I'd have to be blind, deaf and quadriplegic for you to be an actual threat."
The blind alpha offhandedly studies the teenage beta and puts him through a test. He hears Scott's steady heartbeat, noting although Scott is afraid of him, he's controlling the fear. He then plays with Scott that maybe the beta should "rise to the occassion", kill an alpha and become one. Scott replies that he's not a killer, that he doesn't have to kill people. Deucalion answers while he doesn't now, situations where the only way to save one's life is to take another.
Scott: "What do you want?"
Deucalion: "I want to see what you're made of."
The elevator stops and residents walk in while Scott quickly slips out. Deucalion nonchalantly asks for someone to hit the button for the penthouse where he and his pack are living.
Deucalion is eventually contacted by Scott who tries to diffuse the bad blood between the two packs. He arranges for he and the lead alpha to meet and talk at an abandoned superstore.
Derek: "Him. Just him."
Deucalion: "Just me? Now, how does a blind man find his way into a place like this? All on his own?
After Deucalion speaks, the rest of the alphas come out of their hiding places and converge upon the smaller betas. Deucalion broke the rules of his meeting with Scott as well.
The atmosphere is tense and quiet for moments. An obstinate Derek makes the first move, targeting Deucalion, but Kali swiftly knocks him back. A full-on fight erupts between the two packs while Deucalion, serene as ever, observes from the escalator. The super-powered alphas make quick work of Derek and his betas.
Arrows, flashbangs, suddenly rain down on all around the assembled werewolves. Deucalion orders his Alphas to cover their eyes. As both Packs recover, a standoff occurs between Scott and Ennis. Both Wolves ram into each other - Scott matches Ennis' charge with equal super-strength and afterwards he briefly sports the red eye color of an Alpha which Deucalion catches.
With Derek and Ennis falling off the edge of the floor to their apparent deaths two floors below, the battle ends with Packs dispersing. Ennis is alive and has been brought to Alan Deaton's animal clinic for treatment.
Deucalion then lies to Kali and the twins, telling them that Ennis died from his injuries. His goal is now to enforce his Pack's own code: Derek has to join their Pack in repentance for Ennis' death or he must die+. To this end, he entices a vengeful Kali to push Derek into this corner.
In Beacon Hills high school, Deucalion is in the music room. By tapping his cane against the teacher's desk in a fixed rhythm, he discretely sends a message to Scott, luring him to the music room. He knows Deaton has been abducted by the Darach. He compares Scott's situation with a tempo being set, but a metronome is missing thus the rhythm is not steady. He offers to help Scott recover his "metronome" - helping Scott find Deaton.
Scott leaps at the Alpha taking him on. He tries multiple acrobatic feats against the older werewolf, but Deucalion outmaneuvers and outmatches him at every turn. Deucalion then takes out the dagger in his cane and stabs Scott.
Deucalion commends Scott on his abilities, but reminds Scott that Deucalion isn't the one who's kidnapping and sacrificing innocent people. But his Pack does want Derek dead however, reminding Scott of Kali's vendetta. He lets Scott know the chances are that someone is going to die. Unafraid, Scott demands that Deucalion tell him where Deaton is. Amused, Deucalion tells him a very important clue instead: "Let the current guide you."
Deucalion and Kali come upon Melissa McCall who curiously pulls the former's cane out of the wall. From behind, he takes the cane out of her hand and gives her his thanks. Melissa nervously realizes she's talking to the bad guy. The Alpha humors her, saying she has no idea of how much of a bad guy he is. He takes her hostage.
When they don't comply, Deucalion's Pack track Jennifer throughout the building. Kali gives chase on Jennifer and Derek. They escape into the elevator. Deucalion, however is prepared for this as he turns off the power generator, leaving the elevator stuck in the shafts.
He thanks Melissa for her cooperation. Melissa asks him what does he want with her now. Deucalion answers she's his gesture of good will and lets her go, telling her to go find Scott and advises her to be careful, to her confusion.
Kali mocks Deucalion that he has a soft spot for Scott. Deucalion answers her the young Beta is an investment he's trying to mature. He tells Kali while they're talking about the soft spots, he requests they talk about Jennifer Blake. He's aware Kali has recognized Jennifer is actually her former emissary Julia Baccari.
The lead Alpha goes on to cajole her on how harmless Julia looks now. Kali arrogantly admits there might have been a moment of when she was sure Julia was still fighting for life that she could have finished her off or just walked away and let someone she loved die in peace. Deucalion mockingly tells Kali his heart bleeds for her, but scolds her that Julia's could have bled a little more.
Deucalion listens to Scott's allies as they plan how to get Jennifer and Cora out of the hospital right out from under his Pack's noses.
Up on the hospital roof, a terrified Scott calls out for his mother. Deucalion arrives, telling Scott Jennifer took his mother, because as a parent, Melissa is a Guardian. The Alpha tells him he could have told him what 'Guardians' meant. Deucalion makes his terms clear: Scott joins his Pack and help him catch Jennifer; he'll help Scott rescue his mother and Stiles' father.
With a heavy-heart, Scott complies, ignoring Stiles' protests. Scott follows Deucalion into the night. Later on, Deucalion lets out a howl to tell the others to retreat.
Kali and the twins have cornered Morrell who's cast a mountain ash circle. Deucalion interrogates Morrell how she knew the Pack would come for her. Morrell tells her former Alpha she was aware that he's always been suspicious of what druids could do and that their reliance on her has been questionable because they know she hired the female warrior (Braeden) who rescued Isaac from them. The Alphas want her for information on Jennifer. Morrell replies she knows nothing more than they know.
The lead Alpha remarks "the lies people will tell when begging for their life". He then uncaps his cane and throws it into Morrell's shoulder knocking her over her circle.
The Alphas advance on Morrell, but Scott intervenes, tells his new Pack members no and to back off. In the end, Morrell's life is spared.
Deucalion meets with Scott atop Lookout Point at the night of the full moon and the lunar eclipse as Jennifer plans to kill all the Alpha Pack when werewolves everywhere are simultaneously powerless and she has already killed Kali and the twins are dying. Scott comes up with a plan. He leads Deucalion to the same abandoned building where Ennis declared vengeance. Scott sends a MMS video to Jennifer of the spiral carved into the wall knowing it's her true intent.
Scott and Deucalion wait. Jennifer arrives, along with a pressured Derek in tow. Jennifer had promised him the kidnapped parents if he would be her Guardian. Deucalion amusedly calls the standoff "brother against brother".
"Did you gather your herbs? Pray to your ancient gods and your oak trees? Slit a baby's throat, perhaps? Should we show them why you needed to sacrifice twelve innocent people just to face me? Or is it fifteen, now?"
The Demon Wolf then advances on Jennifer and shapeshifts into an ominous-looking demonic werewolf shape. Scott, Derek and Jennifer are terrified at this display.
Derek makes the first move, shifting and roaring. The newly regressed Beta werewolf attacks Deucalion, but the Alpha swiftly blocks Derek's strike and left hand, being easily outmatched, and the Demon Wolf knows it.
Jennifer moves in and directs a telepathic blow at Deucalion. He easily resists and shakes the blast off. Cackling, the Demon Wolf then, in the blink of an eye, catches both she and Derek by the throats and lifts them both up. He knocks Jennifer down and duels with Derek again. Derek is overpowered and the Alpha easily flings him aside.
Jennifer advances again, but she's thrashed twice by Deucalion, and is then incapacitated. Scott has been motionless the entire time.
Deucalion runs out of patience and rushes over to Scott, grabs him and forcefully walks him over to Jennifer, saying maybe Scott just needs a little guidance. Scott tells Deucalion to wait, that he forgot to tell Deucalion something he learned from Gerard: "Deucalion is not always blind."
Scott sneaks three flashbangs out of his pocket, and throws them against the floor, setting them off. Able to see in his werewolf form, Deucalion is now truely blinded by the devices. His new disability lasts until the lunar eclipse arrives.
Deucalion panics when the eclipse arrives, knowing he's lost his advantage. Jennifer has disappeared. She later reappears in her actual form, the Darach.
Jennifer has the power now and ruthlessly attacks, pummels and thrashes Deucalion, who's unable to do anything. He lays on the floor barely cognizant from his head injury. Jennifer prepares to give the Demon Wolf the final blow, but Derek stalls her by telling Jennifer that Deucalion doesn't know the price she paid from his bringing Kali into his Pack. Jennifer acquises, playing into Derek's trick to have Deucalion actually see what happened to her.
When Jennifer removes her hands, Deucalion blinks and is astonished, surprised, shocked that he can see again with human eyesight.
Jennifer then demands that Deucalion look at her to see the result of his crimes, before she kills him. The depowered Alpha looks at her scarred, depraved, dehumanized face, to his horror. Jennifer however has been rendered weak by her healing him, as Derek had intended.
When the lunar eclipse passes, and Jennifer recovers her power, she casts a mountain ash circle. Soon her quintuple sacrifice will be complete, and then she won't need a lunar eclipse to kill even Deucalion. Scott however takes action and forcefully pushes against the mountain ash, fully determined to stop Jennifer. Scott keeps pushing on and on, breaking the suprnatural barrier. A newly empowered Deucalion watches in awe, inspired at this display and witnesses as Scott fully awakens his True Alpha status, fully overcoming Jennifer's barrier.
Scott seriously says he's now an alpha and demands Jennifer stop the storm or he'll kill her himself.
Reminded of his humanity and truthfulness, Deucalion steps in, saying killing her won't change his werewolf eyes. So the alpha decides to prevent Scott from becoming a killer, and does it himself, slashing Jennifer's throat, mortally wounding her. Jennifer falls back, incapacitated, as her true form. The storm stops with Jennifer's threat put to an end.
The two Wolves then leave a solemn Deucalion alone.