CBS Officially Confirms The Return Of Tracker's Most Complicated Character

Published Sep 28, 2026, 11:00 AM EDT

Antonella Gugliersi (she/them) has been a feature writer for Screen Rant since 2021. While studying for her bachelor’s in Economics & Management, they started writing about movies and TV shows for Turin-based The Unconventional Mag. After a brief internship at TPI, she decided she wanted to pursue journalism and graduated with a degree in International Journalism from Brunel University.

One all-but-straightforward character is officially set to return in Tracker season 4. While heavily focused on following Justin Hartley’s Colter Shaw’s adventures across the country, Tracker always featured a small ensemble of characters orbiting around him. From the trusty lawyer Reenie, who kept Colter out of trouble countless times in Tracker seasons 1 through 3, to Bobby’s replacement, Randy, without whom Colter’s cases would be very difficult to solve, to newcomer Mel, who proved a valuable addition, Tracker made a point to focus also on memorable characters beyond Colter.

Tracker season 4’s cast changes promoting Mel and Randy to series regulars will inevitably play a role in raising their visibility and importance even more in the upcoming season. However, beyond the friends supporting Colter with his rewardist job, Tracker also featured his immediate family time and time again. It’s already confirmed that his brother Russell will return in Tracker season 4 despite the tricky discovery in season 3’s ending that pushed him to leave Colter abruptly and without even saying goodbye.

Despite appearing in a handful of episodes, nothing is known about whether Mary Dove Shaw and Dory Shaw will be among the Tracker secondary characters returning in season 4. What has instead been revealed is that someone else who has often been an ally of Colter will come back in Tracker season 4. Indeed, Billie Matalon is set to return to Tracker season 4. Still, it’s unknown whether that will actually be good for Colter, given how willing she was to betray him when their interests didn’t align.

Justin Hartley Confirms Billie's Tracker Season 4 Return

In an interview with TV Line, Hartley was asked whether Sofia Pernas, who is also his wife, would return as Billie in Tracker season 4. Hartley confirmed that she will, adding that “part of the fun of our show is to get these recurring characters that come back and pop in and do meaningful stuff from time to time.”

Hartley didn’t specify when Billie will return in Tracker season 4, only that she will. However, his focus on the importance of bringing characters back not just for the sake of it but because they serve the story in some way hints at her return being impactful on more than just Billie, fitting the overarching story that Tracker season 4 purports to tell.

Billie was last seen in Tracker season 3, episode 20. Her case brought her to the same shop that Colter was casing in the hope of finding two missing young women. Billie and Colter finding the missing girls and the laptop with incriminating blackmail information meant they both solved their cases, bringing them on the same side despite working for different clients. Their history nevertheless made Colter wary of leaving the laptop with Billie, and his reaction during their celebratory dinner highlighted how he could still not completely trust Billie.

Why Billie Is Tracker's Wildcard Character

Paramount Press

Billie was officially introduced as Colter’s competitor in the first episode she appeared, in Tracker season 1, episode 6, “Lexington.” Both tasked with finding a missing racehorse, Argo, Colter and Billie initially tried to solve the case without collaborating. They eventually had to, and managed to solve the case without any double-cross. Still, the threat hovered over them, and when Colter proposed celebrating together, Billie kept her distance. Billie’s untrustworthiness was established from the get-go, with Colter wary of her because of what happened during the MacPherson case, one never shown onscreen, during which Billie betrayed Colter.

Tracker season 1, episode 6 also introduced Colter and Billie’s romantic connection through their almost-kiss. That added another level to the complicated relationship, but every time since then that Colter had to rely on Billie, she came through. That was the case even when she had to infiltrate a prison to help Colter in Tracker season 2, episode 15, putting herself in physical danger, or when Billie ended up being arrested for protecting Colter as the police were looking for him in Tracker season 3, episode 10.

While Billie often bolted right after a case together, she also always supported Colter when he asked for her help. Still, her original betrayal and values perceived as dissimilar often made Billie untrustworthy. This makes Billie a difficult character to understand in Tracker, as her actions paint her as someone to be trusted, but she also doesn’t open up, making her past cast a long shadow over her. Hopefully, Tracker season 4 can reveal more about Billie with her scheduled appearance, finally making the character a little easier to understand.

Source: TV Line

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