Justin Hartley Has Another This Is Us Reunion on Tracker with Jennifer Morrison — See Their Moving Scene! (Exclusive)

Justin Hartley and his former This is Us costar Jennifer Morrison are reuniting on the Tracker season finale.

On the Sunday, May 19, episode of the CBS drama series, Colter Shaw (Hartley) “investigates the disappearance of two amateur storm chasers, one of whom is the daughter of an old family friend (Morrison), that the local police have written off as an accidental drowning,” according to a synopsis from the network.

“Colter’s expert tracking skills lead him to uncover the seedy underbelly of a small town resort,” the description continues.

In an exclusive clip from the season 1 finale, the family friend Lizzy Hawking tells Colter that her daughter Katie and her boyfriend went missing after taking a boat out to set storm trackers.

“They left late Friday afternoon. I talked to Katie right before they went out,” she explains. “There was a big storm coming in and they wanted to be ready.”

Colter says her daughter’s work as a storm chaser is “impressive,” Lizzy counters that it is “terrifying” as her mother.

When asked if Katie takes risks, she explains, “The most traumatic stuff gets the clicks out.” She then notes that Katie doesn’t have the support of local authorities. “Sheriff Woods is always giving them trouble saying that Katie's storm tracking is pointless risk-taking. But what he doesn't get is that she loves it, risks and all. And she's good on the water, she can handle herself.”

She adds that her daughter's boyfriend Dylan is a “third generation Waterman. Surf, Scallop diving, he basically grew up in the water.”

“That's good, it increases their chances in case something unexpected happened out there,” Colter explains.

When she asked what he meant, he shares, “Well, I followed the storm track and there was a lot of places that boat could have landed — if in fact they were out on the water — when the storm hit.”

After asking if there are any more details about the disappearance, Colter promises, “Lizzie, if Katie's out there, I'll find her.”

Hartley previously teased in an interview with Collider that Morrison, 45, would be playing a “key role” on Tracker. 

“I haven’t worked with her since This Is Us, and she comes on as an old family friend of Colter’s, from way back when they were kids,” he shared earlier this month. “And so, that whole family dynamic leaks out a little bit through her experience with him in the finale. So, there’s that. I probably wasn’t supposed to tell you that, but it’s all good."

As This Is Us fans may recall, Morrison played Cassidy Sharp, a military veteran who grew close to Hartley’s Kevin Pearson.

This is not the first This Is Us reunion on the CBS series. Jon Huertas directed the April 21 episode, titled "Aurora."

When PEOPLE caught up with Hartley, 47, prior to the Tracker series premiere in February, the actor was more than excited to tease his reunion with Huertas. 

“I'll be with him every day on set,” Hartley said. “We'll be spending a ton of time together.”

Hartley also previously shared with PEOPLE that he is still very much “in touch” with the rest of his former on-screen family.

“All those guys! Sterling [K. Brown] and I just got a little video message from Mandy [Moore]. She was doing something ridiculous and it felt like she might've been making fun of us. She probably was,” Hartley said with a laugh. “I love them.”

Never miss a story — sign up for PEOPLE's free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from juicy celebrity news to compelling human interest stories.

The season finale of Tracker airs Sunday, May 19 at 9 p.m. ET on CBS and streams on Paramount+.