'This Is Us' Star Justin Hartley Gives Clue to What's Coming During Season 3

Justin Hartley is dropping some hints about what season 3 of This Is Us will look like. In an interview with Entertainment Tonight, the 41-year-old star said his character Kevin will retrace Jack's (Milo Ventimiglia) footsteps in an effort to better understand his late father.

"I think he's retracing some of his father's footsteps a little bit and trying to find closure and get information about things he doesn't quite know about," Hartley said.

In the final minutes of the last episode of season 2, viewers saw Kevin on a plane flying to Vietnam, where his father served in the Army during the Vietnam War before getting married and starting his family. In the scene, Kevin is seen holding a photo of his late father during his time in the war. The photo was first shown in an earlier season that showed two flashback during the "Brothers" episode. It shows Jack with his fellow troops, including his brother Nicky.

Fans are excited to potentially learn more about Jack's brother, Nicky, who remains one of the show's biggest mysteries. In season two, it was revealed Nicky served in Vietnam with Jack and was presumably killed in the war. Following the Super Bowl episode, Ventimiglia said that that while his character would not be moving forward in the show's timeline, his past would continue to be explored on the show, including his relationship with his brother.

"It's been a question, what Jack's younger life was like, what his influences on having a positive family experience were," the actor said. "A lot of that relies on his relationship with his brother and what they experienced in the house they grew up in."

"For Jack and Nicky, I think a lot of that probably will be played not so much on younger child actors that are playing those parts that will rely on myself and another actor stepping into the shoes of Nicky — their time as young men, their time in Vietnam, the knowledge that maybe Nicky didn't quite make it," Ventimiglia shared.

This Is Us viewers never did get to see Jack in Vietnam during season 2, although his time there was teased with photos and stories a few times throughout the season. Ventimiglia told PEOPLE that fans will "definitely" see Jack "in the Vietnam era."

"At the end of the Super Bowl episode when people were ultimately confronted with how he passed away, there was a trailer to show Jack in a helicopter over Vietnam in uniform. We're going to explore that side of Jack's 20s and what brought him into the man that we all knew," he explained.

As Ventimiglia said, after the famous Super Bowl episode that revealed Jack's cause of death, there was a brief shot of Jack in Vietnam. Some thought we would see that scene in subsequent episodes, but it was not to be.

Despite Jack meeting his maker during the series' post-Super Bowl episode, the narrator says in the promo that "Jack's story has just begun," with the promo showing two soldiers on board of a carrier plane, both holding guns. The camera then pans to one of the soldiers, which turns out to be our very own Jack Pearson.

Although much of season 2 focused on how Jack died, it sounds like season 3 may focus on how he lived.

"There are so many questions with Jack," Ventimiglia told Esquire in February. "His upbringing, what happened to him in Vietnam, what happened to him after Vietnam before he met Rebecca? And those early days of Jack and Rebecca, I know is an era that [series creator] Dan [Fogelman] is excited to explore."

This Is Us resumes production in July. Season 3 of This Is Us will air in the fall on NBC.