Colin Ferguson, is a U.S. Marshal who reluctantly ends up as the sheriff of Eureka. Jack is consistently dumbfounded by the wonders Eureka produces, as well as its propensity to produce things that often threaten the entire town (or world). Despite being a man of average intelligence in a town full of geniuses, Jack's admittedly simple ideas and his intuition often save the day. Zoe Carter, portrayed by Jordan Danger (seasons 1–3, recurring in seasons 4–5), is Jack's rebellious teenage daughter. Unlike her father, she is intelligent enough to keep up with the town's residents. Yet, like her father, she possesses street smarts, something lacking for most of the town's residents. She hopes to attend Harvard Medical School and become a physician. Dr. Allison Blake, portrayed by Salli Richardson-Whitfield, is a Department of Defense agent who acts as the liaison between Global Dynamics and the federal government in season one. Later, she becomes the head of Global Dynamics. In seasons four and five she is the head doctor due to the effect of their journey to the 1940s. Allison, unmarried, is also mother of Kevin, who has autism until time travel in season four creates a new timeline where Kevin is neurotypical. Dr. Henry Deacon, portrayed by Joe Morton, is the town jack of all trades and a brilliant scientist. Henry has ethical objections to the kind of research conducted at Global Dynamics, so he prefers to be employed as the town's mechanic. Henry's assistance is often invaluable in defusing the bad situations that are created by experiments at Global Dynamics. In seasons 4 and 5, he is far more directly involved in the operations of Global Dynamics and in two occasions he becomes its head, the first time replacing Stark in season 1, and in the end, Fargo. Dr. Nathan Stark, portrayed by Ed Quinn (seasons 1–3), is one of Eureka's top scientists. He and Jack are frequently at odds, although both respect each other. On and off, he is romantically involved with Allison. He is modeled after Tony Stark, a Marvel Comics character. Dr. Beverly Barlowe, portrayed by Debrah Farentino (seasons 1–2, recurring in seasons 4-5), is the town psychiatrist. She secretly works for a mysterious organization known as the Consortium, which has expressed a desire to exploit Eureka's innovations by whatever means necessary. Josephina "Jo" Lupo, portrayed by Erica Cerra (recurring in seasons 1–2, regular in seasons