This Is Us' Justin Hartley on the Heartbreaking Finale and What's Next

This Is Usdelivered a fall finale that still has a lot of fans reeling.

The Pearsons came together to celebrate Christmas together at Randall's (Sterling K. Brown), which included a surprise visit from Toby (Chris Sullivan) who flew all the way to New Jersey to tell Kate (Chrissy Metz) that he couldn't live without her. Unfortunately, the couple's sweet reunion was interrupted by tragedy when Toby collapsed in the Pearson living room. The final moments of the episode showed Toby flat-lining on an operating table and doctors rushing to try and revive him.

Now the major question remains whether Toby lives or dies. Either way, the Pearson family will have to find a way to move on, and figure out how to support Kate as she deals with this tragedy. To find out how Toby's situation will affect the Pearsons and what's coming up in the second half of the season, we chatted with Justin Hartley, who plays Kate's brother Kevin on the show.

What was the feeling when you found out what would happen to Toby?

Justin Hartley: I was pretty shocked -- I didn't see it coming. You know, it was that typical a-la-This Is Us style where they sort of give you that cliffhanger at the end. You'd think that by now I would've seen it coming, but I didn't. And poor Toby, man! I mean of all people, he's a good guy!

How will this affect Kevin and Kate's relationship? Will it make them closer or will she push everyone away?

Hartley: I think whenever any kind of hardship or tragedy comes along, it usually pulls a family closer together, or at least hopefully. These two are already so insanely close that I think he feels a lot of her pain and he wants to be there for her, and so it will probably keep them as close as they ever were. He'll try to be there for her as much as he can.

What can you tease about Kevin and Sloan's relationship in the second half of the season?

Hartley: It gets a little bit complicated, as does any relationship that you have with somewhere where you're sleeping with each other but also working together. They're doing this play and they're working together all day, while they're trying to have this relationship. There might be other players involved too. Things get complicated pretty quickly.

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What is the biggest difference between Kevin now and the Kevin we met in the pilot?

Hartley: I think a lot. For one, I think he's grown up quite a bit. I think he's taking responsibility for things. He's becoming a man of action instead of just sort of feeling sorry for himself. As far as the play goes, instead of just complaining about the play and not really wanting to do it, he's becoming a man of action where he decides that he's going to put up his own money and he's going to produce the play and do it the way he wants to do it. So he's becoming quite the problem solver, I think.

What is Kevin searching for on his journey to be self-fulfilled?

Hartley: I don't know if he's aware of it or not, but I think it's love. I think it's the same thing we're all looking for, but I don't know if he's aware of that. I think he's trying to fill it with other things like success at work, which is great, but I think he's looking for love and companionship and someone to share life experiences with. I'm just not sure that he's aware of that yet. He knows there's something missing, he just doesn't understand that it's companionship.

Who on the cast would you like to get a chance to work more with?

Hartley: I would say Milo [Ventimiglia], because I never get to work with Milo at all, so I'd like a chance to work more with him! That would be fun. I get to work with everyone else, which is kind of cool.

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What has been the most emotional moment of this show for you?

Hartley: There've been so many! A couple of them we haven't aired yet. I really enjoyed the painting episode, where he's explaining the painting to the kids. You know, what his play was about. Also when he finally opened up at the funeral to that widow about his dad dying and about why he wears that necklace. That was pretty emotional.

What are you most excited for fans to see in the second half of the season?

Hartley: I'm looking forward to their reaction when they see what's in store for Kevin. I want to see how this play goes -- how successful or unsuccessful this play ends up being. I'm excited to see the evolution of his relationship with Randall. Also if he finds what he's looking for and how long that takes him, and where it was this whole time.

This Is Us returns Tuesday, Jan. 10 at 9/8c on NBC.