CBS has announced a cast change for Cassady McClincy Zhang in Tracker season 4.

According to Deadline, the actress, who has recurred since season 3 as Reenie’s new hire Mel, has now been promoted to series regular, joining Justin Hartley (Colter Shaw), Fiona Rene (Reenie) and Chris Lee (Randy).

Based on The Never Game by Jeffery Deaver, the procedural series follows Colter, a lone survivalist who uses his instincts to find missing people and collect rewards, and is supported – typically remotely – by Reenie and Randy.

Season 4, which is set to begin on Sunday 4 October on CBS in the US, will continue to follow Colter as he travels to help people in difficult situations, with the first episode set to focus on "Colter’s search for a teenage boy’s missing father, which leads him to a dangerous criminal operation at the Port of Los Angeles".

CBS previously released the official promo for the upcoming instalment, showing Colter in action. You can watch the clip below:

Hartley previously teased that season 4 will be the most ambitious one yet.

"We’ll come back with something – we already have it, it’s pretty incredible," he told TheWrap in May 2026.

He added: "Honestly, I think it’s our most ambitious season to date, but I think it’s also our richest one, in terms of character and backstory and where we’re taking Colter."

Tracker first premiered on CBS back in 2024 and has become one of the platform’s most-watched shows on the network in the last few years, with fans praising the series’ case-of-the-week-style procedural format.

Tracker season 4 is expected to stream in the UK on Disney+. Seasons 1-3 are streaming now. You can sign up to Disney+ from £4.99 a month.

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