Everything from the episode "Fata Morgana" that isn't tearjerking. The team travels to a crypt in an island off the coast of Scotland; after defeating the crypt keepers they find three women in comatose state. They bring them back to the Sanctuary for care, where it is determined that the sisters have been held prisoner for 1,200 years. After they awaken, Will tries to help and comfort them, mostly because he thinks they're a little crazy in the head. It turns out the sisters are the Morrígan, who were created with the intention of destroying man. In the meantime, a group of mercenaries known as the Cabal have found out the Morrígan are missing and in order to regain what they see as their "property" head to the Sanctuary ready to kill. During the fight between Magnus and the Cabal, Will desperately keeps trying to teach the sisters to fight for their freedom. When the team is surrounded by the mercenaries the sisters surrender to the mercenaries who in exchange spare the team's lives. Will believes his teachings of freedom may have gotten through to them after all.
From "Revelations": Two times two equals infinity.