Sheriff Jack Carter (Colin Ferguson)Jack Carter is the sheriff of Eureka, a community in the Pacific Northwest planned by President Harry S. Truman as a place for America's most brilliant minds to work on breakthroughs in science. It is populated by geniuses and strange things occur on a regular basis due scientific experiments gone awry.Although Jack is only of a slightly above average intelligence this is an asset in a community of complicated thinkers who tend to miss the bigger picture.Jack is handsome, athletic, morally upright, open to possibility, determined to do good, an excellent observer and deeply intuitive. His ability to make connections and solve problems in a way that others cannot makes him invaluable to Eureka.He often works closely with town mechanic Henry Deacon. He sometimes has contentious relations with his deputy Jo Lupo since their approaches to law and order are very different but they have mutual respect for one another.Jack was once married to a woman named Abby and they have one daughter named Zoe. Although she sometimes acts out impulsively, they have a good relationship and he is fiercely protective of her.Prior to becoming sheriff Jack was a U.S. Marshal. He enjoys baseball and has trouble keeping cars intact.