Season 3 of Justin Hartley's hit series Tracker is coming to an end. Based on Jeffery Deaver's novel The Never Game, Tracker centers around Colter (Hartley), who travels the country helping to find missing people (or sometimes dogs) and solving cases others couldn't or wouldn't. Hartley, 49, also serves as an executive producer and has hinted at how far the show will push his character. Three seasons in, the CBS series has found success with a mix of intense cases, familiar guest stars and Hartley at the center of it all.