Tracker got viewers invested in Justin Hartley's Colter and the rest of the Shaw family - but how are the characters related to each other amid multiple cast exits? The hit CBS series, which premiered in February 2024, focuses on fictional survivalist Colter Shaw (Hartley) as he travels the country to help solve various missing persons cases. A side plot centers on Colter's family life - including how his dad Ashton's mysterious death might have been at the hands of someone Colter knows.