CBS's action drama Tracker is set to return for its fourth season, with the streamer confirming a key casting change ahead of the premiere, which is less than a month away. Cassady McClincy Zhang, previously a recurring guest star, has been promoted to series regular, joining leads Justin Hartley, Fiona Rene and Chris Lee. The move signals an expanded role for her character in the new episodes, as the show builds on its strong ratings and critical reception since launching in 2024.

The new season picks up after a dramatic finale, with lead character Colter Shaw, played by Justin Hartley, confronting difficult revelations about his family while continuing his work tracking missing persons for reward money. Zhang, known for her role in The Walking Dead, had previously appeared as Mel, assistant to Fiona Rene's character Reenie. Tracker, based on Jeffery Deaver's novel The Never Game, premiered in February 2024 to an 89% Rotten Tomatoes approval rating and strong viewership after airing post-Super Bowl LVIII, with its renewal for Season 4 confirmed in January.