In Melissa Roxburgh's Tracker Encore, Colter Gets His Hands On Dad's 'Genius' Work — Does It Contain Smoking Gun?

Fresh off Season 1 of NBC's The Hunting Party, Melissa Roxburgh reprises her role as Dr. Dory Shaw in the penultimate Season 2 episode of CBS' Tracker — and TVLine has an exclusive clip from her return.

Roxburgh first guest-starred in Tracker Season 1, Episode 11, one week out from Jensen Ackles' own debut as Colter and Dory's brother, Russell. Though Ackles managed to squeeze in a second appearance early in Season 2, Roxburgh had not been back — that is, until now.

As you'll recall, Dory followed in Ashton and Mary Shaw's footsteps and became a college professor. But unlike Colter, who was determined to get to the bottom of what really happened the night their father died, Dory was determined to leave the past behind and get on with her life... or so we were led to believe.

Two weeks later, in Tracker's Season 1 finale, Jennifer Morrison's Lizzy dropped a pair of bombshells: Years ago, Ashton worked with Lizzy's mother. First they were coworkers, then they were lovers. What's more, Lizzy's mother was in possession of a file box full of Ashton's research papers — a box Lizzy had already turned over to Dory.

In the scene embedded above, Dory delivers Colter the aforementioned box. "There's a lot of research, notes... but there's no smoking gun," she says. What it does contain is Ashton's work on zero point energy, which Dr. Shaw tells us is "ahead of the curve."

"He was always talking about people trying to steal his ideas," Colter reminders her. "Lizzy said that her mother and our dad got into a fight the night that he dropped the box off. I'm thinking maybe it was because he was pressuring her to do something with it because he'd lost his academic credibility.... I can't help but think that there is something in that box that's connected to what happened to Dad the night he died."

Will he finally get his answer by season's end...?

Tracker airs Sunday at 8/7c on CBS (and streams next day on Paramount+). The Season 2 finale follows May 11.