Michael Hogan as Gerard Argent -Human(Hunter)-
Gerard Argent is Allison’s grandfather, Chris and Kate’s father, a lethal werewolf hunter and the main antagonist of Season 2. Gerard is ruthless, crafty, deceitful, monstrous and shows no remorse for any life he threatens or takes, even members of his own family. He first arrives in Beacon Hills for his daughter Kate’s funeral, though later Gerard declares vengeance for Kate’s death; he kills an innocent werewolf the hunters trapped, declares that there is no more code and that the Argents will kill all werewolves they find, regardless of their innocence.
In “Shape-Shifted”, Gerard goes undercover as the principal at Beacon Hills High. When Gerard finds out that Scott is a werewolf in “Abomination”, he blackmails Scott into following his orders by threatening to kill Scott’s mother. Scott complies supplying him with information and becoming a member in Derek’s Pack. Gerard heartlessly endorses that Victoria must kill herself after Derek Bites her and uses her death to emotionally manipulate Allison into joining him. In “Fury”, Gerard kills Matt Daehler and becomes the Kanima’s new Master. He then steps up as the main threat, threatening Melissa McCall’s life again, and abducting and beating Stiles as a message to Scott. In the Season 2 finale, during the showdown at the industrial warehouse between Scott, Derek, Isaac, Chris, Allison, and Jackson as the Kanima, Gerard surprisingly has the Kanima hold Allison hostage. It comes out that Gerard he has cancer; all his scheming and his genocidal campaign of werewolves was all a ruse for to push Derek into a position to Bite him, become a werewolf, kill Derek to become an Alpha, and ultimately cure himself. He has the Kanima threaten to kill Allison unless Scott has Derek Bite him. Chris is incensed at his father’s betrayal calling him a monster, that he pushed for Victoria’s suicide all while what he was planning to do and threatening his daughter’s life. Gerard fires back at Chris he’d kill his own son if it meant survival. Scott follows his orders. However, because of a plan by Scott, he and Deaton had replaced Gerard’s cancer medication with mountain ash filled capsules: his body violently rejects the Bite, black blood eschewing out of his ears, eyes, nose and mouth and he is incapacitated, but he disappears.
During Season 3, Gerard is shown to be alive, in hiding and living at a medical institution. His cancer is now vanished, but is confined to a wheelchair and still suffering the effects of the rejected Bite from the second season, black liquid still pouring out of his orifices. He reveals to Chris that one of their family members in 1977, Alexander Argent, his own brother, was bitten by the Alpha werewolf, Deucalion. In “Visionary”, Allison and Scott come to him for information about Deucalion’s Alpha pack in exchange for Scott siphoning away some of his pain. Gerard lies to them about Deucalion ambushing him and killing his men when they met with Deucalion’s pack during Deucalion’s proposed peace offering, when it was actually Gerard himself who ambushed all involved parties, killing Deucalion’s Pack members and killing his own men because they wanted peace with the Packs (which Scott catches onto). He’d also stabbed Deucalion in the eyes with two arrows which caused Deucalion’s blindness. However, he truthfully told them that while Deucalion is blind, he can actually see in his werewolf form. Scott threatens Gerard; if he finds out that the story he told them about how Deucalion truly lost his eyesight was a lie, or his lies get innocent people hurt, he’ll come back to “take away more than (Gerard’s) pain”. It is because of Gerard’s treachery, that Deucalion’s Alpha Pack was formed, and Deucalion is the sociopath he is in the present.