|Ability||Immune to Troubles and can create troubles|
|Last Appearance||"A Matter of Time"|
|Appeared In||10 episodes|
William is "a mysterious stranger" whose secret agenda leads him to FBI agent-turned-cop Audrey Parker. His mission is to turn Audrey back into her own original self. He was the main antagonist of season 4.
In the barn
William discovers Audrey who is a waitress/bartender in a bar called the Oatley Tap Room. Audrey introduces herself as Lexie DeWitt and tells William that she has worked at the bar for about a month. It is apparent that she has no knowledge of her previous life as Audrey Parker. While William and Audrey are talking, a man enters the bar and she notices that he has a gun. Audrey doesn't want to deal with the man herself, yet William appears to not really care and asks her for quarters for the jukebox. She goes to the table where the man with the gun is. He pulls the gun on Audrey and tells her to sit down. Audrey tells the man there is no money in the bar and he responds with he doesn't want any money. Before he can tell her what he does want, William comes from behind and disarms him. The man runs out of the bar. Later William tells Audrey that the man was after him because he didn't want him to tell Audrey the truth. That she isn't really Lexie at all but someone completely different.
Audrey notices that William is at the bar again. He tells her that she is lucky that he is so determined. Audrey doesn't seem impressed since William is carrying a concealed gun. So William breaks the gun down and puts it in front of Audrey on the bar's counter. Audrey states that she would have felt better if he had kept it intact. As they continue talking the stranger from the first episode comes back with another man. William tells her that this time he may not be so lucky. No one will help William even when Audrey asks. Just when it seems like William will be taken, Audrey grabs the pieces of the gun and puts them together and then points them at the two men and tells them to let William go. They balk, and she fires, quite accurately. The two men leave without William. Audrey is very confused with her knowledge of guns, when she had apparently no prior knowledge. Now that William has her attention, he tells her that unless she remembers who she really is, a lot of people are going to die.
Audrey is really confused and angry, and demands that William tells her exactly what he knows. He asks her if she remembers how she got to the bar. She describes a scene with an ex-boyfriend. William asks if she felt it? Audrey replies, "Yes". However, William, says, "You remember the feelings but you don't really feel them. Because they're not real." Audrey talks to her friend Rhonda, another bar waitress and tells her that she's going to go home and wants to get away from William. She grabs a bottle of tequila and Rhonda states, "If this isn't real, then the boss won't mind." Audrey walks out of a back door and a few moments later, she returns through the front door of the bar. Confused, she notices that William is still there and a new batch of bar patrons. It appears to be a new day, to which Rhonda says, "Good morning, Lexie."
Audrey is now totally surprised and states to Rhonda and William both who are exactly where she left them, that she just left them a minute ago. Rhonda thinks she is joking and might be trying to get a day off. Audrey goes to William and says he really needs to tell her what is going on.
Up to this point, everyone thinks that Audrey has been pushed out of the barn. William tells her that the bar is just another name for the barn and everyone in it isn't real. He tells her the Barn is dying and if they don't hurry, it will take her with it.
William is able to convince Audrey that people are looking for her in Haven due to voices coming from Haven into the bar. On top of that, she starts to hear a fog horn which is an indicator to where the door is that will get her out of the bar and into Haven. With a bit more convincing and indicating that Audrey will need to make a "Leap of Faith", Audrey jumps through the door upon seeing Nathan and her friends on the other side from the Haven door. At this point we don't know what becomes of William. We only know that he says that he and Audrey will meet again.
Finally, after weeks of not seeing William. Audrey finds him being held prisoner by the two strange men/thugs from the Barn who had previously threatened him. Soon after the thugs are taken into the police station, strange hallucination troubles take over Nathan, Jennifer, and Dwight. The police station is turned into a mad house with everyone turning on each other until Audrey mistakenly figures out where the box that the thugs want is. William alone with Audrey reveals that he is the boss of the thugs (Sinister Man and Heavy) and the cause of the hallucinations. William causes Audrey to remember her original self by touching her causing a great "spark".
William tries to manipulate Audrey by forcing her to make a Trouble to "silence" a Harker baby that cries. When the baby cries, it causes people randomly to die when they hear its voice. This giving of a Trouble is William's hope to activate Mara, Audrey's original self. In The Lighthouse, Audrey tried to push him into the Door, which brought him back to where he came from, but he grabbed her arm and his spark caused Audrey to be taken over by Mara. Nathan pushed William and Jennifer closing the door, resulting in him being stuck in The Void.
In A Matter of Time, William becomes trapped under a rock and unable to help Nathan remove a rock blocking the entrance of the cave. William, noticing that Nathan was growing weaker and near death, demanded that Nathan give him some Aether spilling from the cracked rock surface; his alleged plan was to give Nathan a new trouble to help remove the rock. However, although Nathan gave William the Aether instead he made one of his minions to remove the rock and release him. Although, being told that Mara was now deceased and that she was only after his Aether, he realized that he always loved her more than she loved him. Nathan gave his ring to allow William to return home.
- "Bad Blood"
- "Lost and Found"
- "The Trouble With Troubles"
- "When the Bough Breaks"
- "The Lighthouse"