Set in Toronto at the turn of the 20th century, the series follows Detective William Murdoch (Yannick Bisson), a brilliant investigator who uses cutting-edge (for the time) forensic techniques—such as fingerprinting, blood testing, and trace evidence—to solve crimes that leave the rest of the police force baffled. Season 2 continues the "case-of-the-week" format but introduces higher stakes and more complex story arcs.