In five seasons of playing Kim Wexler on AMC’s “Better Call Saul,” Rhea Seehorn has been through a lot, with the most recent year upping the ante more than before with a work betrayal, increased relationship stakes, her leaving her law firm and a confrontation with a drug kingpin.

“It was hard to track what was going on inside her head that could make her behave in erratic ways,” Seehorn says. “But all I have to do is sink into everything she’s said and done and I understand why she would behave this way. I said ‘Thank you’ a thousand times to the writers.”

Like Seehorn, many of the performers in this year’s supporting actress Emmy races found themselves at the center of storylines. In the second season of HBO’s “Succession,” only daughter Shiv Roy, played by Sarah Snook, was chosen to run the family business. There were early indicators Shiv would have a big season: The opening credits (home movies of the Roy kids as children) changed so the young Shiv was left standing at the end, for example.

“I didn’t even realize at first,” Snook admits. “I had to go double-check from the first season!”

Of all of Shiv’s storylines, Snook says the toughest was a scene in which she persuades a victim of sexual assault not to testify. “The scene needed to be deeply calibrated. I think a real Machiavellian streak comes out in Shiv in this scene,” she says.

Gugu Mbatha-Raw had a similar challenge in the first season of Apple TV Plus’ “The Morning Show.” She played Hannah, the head booker of the titular show-within-the-show who makes some questionable choices. They include reporting her friend to HR for dating a co-worker in early episodes before it is revealed that she, too, had been assaulted by ousted anchor Mitch (Steve Carell). She was silenced with a promotion, but by the end of the first season shared her story with new anchor Bradley (Reese Witherspoon), only to overdose before her story could be shared with the world.

“Everyone is flawed and you might question her, but as it goes on, you get to see layers of everyone’s motivation,” Mbatha-Raw says. “It was such a gift to be able to work with real, challenging material and to be in safe hands with these difficult scenes. I relished the challenge.”

Even comedies delved deep into tough moments this television season, pushing supporting players more squarely in the spotlight. The fourth season of “Insecure,” for example, saw the relationship between Issa (Issa Rae) and Molly (Yvonne Orji) break down, with events coming to a head during a huge argument in the fifth episode.

“You see it happening and there’s no going back. When you’re hurt, you just see red and go for the jugular,” Orji says. But it was tough to fight with someone she likes as much as Rae. “I was excited to explore this story but at the same time, when we got to shooting, I was like, ‘Wait! I don’t like this!’ It’s great TV, but it hurt not to be talking to her for several episodes.”

In the third season of Netflix’s wrestling comedy “GLOW,” Sheila the She Wolf, played by Gayle Rankin, who usually sports a wig and heavy eye makeup even outside the ring, finally shed her persona. “That was really intense,” she recalls. “Everyone was there and it felt so emotional.”

Rankin says she had been told from the start that the third season would be the charm for learning more about her character, so she doesn’t mind that it took time to get there. “I’m grateful we waited as long as we did because I think it meant that much more to me and the audience. The showrunners knew this was a storyline and a person they really wanted to take their time with.”

Sometimes, actors get an entire episode dedicated to their characters. Such was the case for Hiam Abbass, who plays Maysa, mother to the titular character in Hulu’s “Ramy.” The second season’s Maysa-centric episode, titled “They,” saw her misgender a Lyft passenger and go to extreme lengths to try to apologize to increase her driver rating.

Abbass says it was hard to speak the dialogue because Maysa, while not ill-intentioned, is so clueless. “Who the heck would talk like that,” she says. “Things I would never say in my life. But she’s not mean or racist; it’s just her way of thinking. Her daughter even says to her, ‘You can’t say everything that’s on your mind.’”

Similarly, Uzo Aduba took the focus in the third episode of FX on Hulu’s limited series “Mrs. America.” Titled “Shirley,” after her character Shirley Chisholm, the episode focused on the Black congresswoman’s plight to make strides in politics (including a run for president) amid the fight to ratify the Equal Rights Amendment.

For Aduba, it was important to showcase Chisholm not only on stage, but also in private. “I wanted to find a space where you got to see the woman behind the doors,” she says.

The 2004 documentary “Chisholm ’72: Unbought and Unbossed” was invaluable to her as research, particularly when you see Chisholm release her delegates and “you watch her collapse into her hands and start crying,” she says. “That was the woman I wanted to embrace; that was the story I was interested in telling. So rarely do you get to see a break and just see the person.”