The 43-year-old actor, who directs Tuesday's episode, talks to ET about stepping behind the camera for the first time in nine years.
The Big Three's trilogy officially wraps up with Tuesday's episode, titled "A Hell of a Week: Part Three," and the tension that's been building to teenage Kate's troubles with her less-than-stellar boyfriend, Marc (guest star Austin Abrams), the last several weeks are about to come to a head. While vague clues have been sprinkled here and there in regards to what leads Rebecca, Kevin and Randall to drop everything in order to save Kate from disaster, the latest hour promises to provide some answers about the cataclysmic event involving Marc that dramatically shifts her perspective on her own value and her outlook on relationships. In the present day, Kate and Toby's marriage is on the rocks.
"Pain and suffering," Hartley tells ET when asked the kinds of emotions viewers will feel watching the episode. "I think you'll relate to it in a way where we've all been in a situation that you know you should get out of, in your heart of hearts. And your friends might know it and everyone's just hoping that you make the right decision but you just don't do it. That's where we find [Kate]. It's not a healthy thing and it's not good."
"I don't think that it's one of those things that never happens to people," the actor-director hints. "It's something that happens to people all the time and people are just afraid to speak their mind. Then you see the long-term effect of every relationship you've ever had in your life and it's like, wow, you have the choice and power to make things better for yourself. We see her in that place."
Hartley steps behind the camera for the first time in nearly nine years after making his directorial debut on a 2011 episode of Smallville. The This Is Us star explained why it took him so long to put on the director's hat again. (He's the second series regular to direct an episode after Milo Ventimiglia did it in October.)
"It's one of those things where I was busy acting and focused on that, and it just seemed like the right time," Hartley says. "It just seemed like you have this opportunity to work with these amazing actors who give these stellar performances. The writing's off the hook. The cast is insane. The crew is amazing. I lean on all of those guys and women, and they are there to prop me up. I just felt like if I'm going to get back into it, this is the perfect opportunity to do it with these people -- and I was lucky enough that [creator] Dan [Fogelman] agreed to let me do it. I think we came up with something pretty amazing."
Ever the supportive co-star, Hartley singled out Chrissy Metz's performance in Tuesday's installment, saying "she's never been better," as well as peerless work by Mandy Moore, who he says "will take your breath away," and Chris Sullivan, whose performance he says is "amazing."
"Milo has stuff in this episode that literally... if you thought America was in love with Milo right now, forget it. Forget it," Hartley praises. "It's like you've never seen [him]. You're just going to be like, 'Is this the cutest thing I've ever seen in my whole f**king life?' It's incredible."
When Metz visited the ET stages in January, she said Hartley was “one of my favorite directors I’ve ever worked with.” Hartley equally had glowing things to say about directing his castmates in the critical episode.
"Whatever I'm asking anyone to do commitment-wise, I have to make sure that I'm not only there, but I'm beyond, right? I'm already there and I'm bringing you to the party," he says. "I'm bringing you to the water. I've already dug the hole. I'm not going to tell you to do something that I'm not doing. For me, it wasn't about, especially with Mandy and Chrissy... I never really directed them as much as I feel like I inspired a thought or I put a thought into their head."
Hartley zeroed in on a specific scene between Metz and Moore from the episode where tonally the note wasn't being hit. Instead of beating a dead horse, he opened up and revealed that he shared a personal story with the pair about something he went through in his real life involving his 15-year-old daughter, Isabella, that helped convey the beats he wanted Metz and Moore to reach.
"There was a specific scene where I was trying to get something that I wasn't getting, and it wasn't because the performances [were] off but because I gave a note and the note probably wasn't accurate... I just told them a true story about my life and something that happened and how I was relating to the scene because of what happened to me," he says. "It was very recent and it had to do with my daughter and when it happened, literally it was like clarity immediately. Like, 'Oh gosh, this is huge and this is real and thank God that this just happened.'"
"I told them that story and went back to the monitor and just called 'action.' And every single... they feel everything and they're such good actors. They're full and brilliant, and that little story that I told them, you could see it permeate into the scene and you could see how it affected their performance. Then I got exactly what I wanted and exactly what I hoped the scene needed," Hartley expresses. "I've watched [the episode], of course, and they're brilliant. Those two are blue ribbon, A-plus superstar actors. They really are tremendous... My heart was on the floor."
Hartley also praised Sullivan's work, saying the two had a very brief chat about Toby's arc in the episode before he just got it. "We had a conversation about his character that lasted about 15 seconds," he says. "He looked at me and he's like, 'OK, I like that,' and then he goes and executes it in a way that I never would have been able to explain. This is a highlight of my life working with these people."
This Is Us airs Tuesdays at 9 p.m. ET/PT on NBC.
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