Background Will Zimmerman's maternal relatives are said to have come from
Dublin, Ireland. One of his known ancestors was Jack Zimmerman (Dunne), who served in the
United States Army and was killed in action in
Normandy during
D-Day in 1944. When Will was a child, he was terrorized by a violent creature who killed his mother. However, Will was saved by
Helen Magnus (
Amanda Tapping), who captured it. In the web series, he was a victim of
Bigfoot (
Christopher Heyerdahl) before he worked as a butler in the Sanctuary; Bigfoot liked to scare little children. In his adult life, he worked with the
Federal Bureau of Investigation (FBI), until he was fired for his outlandish theories. He since worked with the Old City Police Department as a
forensic psychiatrist, though his co-workers do not take him seriously there either. Before the series began he had a girlfriend, Meg (
Kandyse McClure), who broke up with him.
Season one The
first season begins with Will investigating the deaths of two police officers; though the police believe they found the killer, Will believes there was a child in the apartment, but his theory was rebuked. He is later recruited by Helen Magnus to join her Sanctuary team, an organization who track down several abnormals around the world and give them refuge at one of their bases, and become her new protégé. She too believes there was a child, Alexei (Cainan Weibe), In the first-season finale, Will has a new love interest; Clara Griffin (
Christine Chatelain), granddaughter of the late Nigel Griffin, Magnus' colleague; Clara shares his
invisibility skills.
Season two In the
season two premiere "
End of Nights", Clara is killed by Cabal superabnormals before their defeat, which greatly affected Will. In an alternate future in the season two episode "
Pavor Nocturnus", which takes place ten years into the episode's future where the world is overrun by
zombie-like creatures after Magnus unknowingly unleashed a virus while curing her
longevity, Will is depicted as the only living survivor of the Sanctuary Network. He did at some point, have a relationship with colleague
Kate Freelander (
Agam Darshi), and had a son, Magnus Zimmerman following the death of the alternate Magnus. He starts his own survivalist group and sacrifices himself in aiding the present Magnus to correct her mistake. While on assignment in
Mumbai, in "
Kali", Will becomes host to a Macri, a creature with a connection to Big Bertha, the most powerful abnormal on Earth. He has the Macri forcibly removed from Edward Forsythe, which leaves him fatally ill. Despite this, Will still maintains a telepathic connection to Bertha, who appears to him as the goddess Kali, and he manages to reach out to her and get her to stop her attacks after Magnus severs Forsythe's connection to her. However,
Terrance Wexford (
Paul McGillion) takes command of the Sanctuary Network, and attacks Bertha, causing her to turn on Will and create three
tsunamis.
Season three In one final effort to convince her to stop, Will is to die so he can encounter Kali, along with two other beings, in an
afterlife to convince them to stop the tsunamis. Kali uses her powers to stop one of the waves, but Wexford badly injures Bertha before she can finish. Will, figuring that the other two beings must be powerful, begs them to save her and his world, which they oblige, after which they resurrect him. Though he at first does not recall the meeting, but later two abnormals are able to access his mind, and he determines that Magnus' father, Gregory (
Jim Byrnes), left him clues leading to
Hollow Earth, an underground area below the surface that is thought to be the origin of the abnormal population. In the next episode, he and the team are resurrected in exchange for helping the underground city Praxis from destruction from its own
geothermal energy. Throughout the second half of the third season, Wil enters a romantic relationship with FBI agent Abby Corrigan. In "
Metamorphosis", it is revealed that on his travels to Hollow Earth, he became infected from a reptilian creature called a Cillobar, and is slowly transforming into one. He gradually loses his inhibitions, and escapes the Sanctuary until he is captured again when Magnus finds a cure to his condition, where he would transform back to human. In the season finale "
Into the Black", Will overlooks the exodus of several abnormals from Hollow Earth, where it is revealed Praxis is destroyed, having been caused by Magnus' nemesis Adam Worth (
Ian Tracey), who attempts to travel back in time to save his dead daughter. Later, Will discovers that Worth made agreements with several abnormal tribe leaders to invade the planet surface. ==Characterization==