"I was Daniel's age and I left a television show. I understand what it feels like to feel like you may be pigeon-holed," Wagner, 58, shared, referring to his exit from the soap opera General Hospital when he was in his late 20s. "He has to do what he has to do and we all learn and grow that way."
However, even Wagner admits that he was "shocked" by the decision, and even a little scared.
"Fear hit me a little bit. It's like when a team loses a quarterback. The team doesn't stop. You're just kinda like, 'How are we going to win with a different quarterback?' And that's kinda the case," he shared.
The move to kill off Lissing's character -- thus eliminating the possibility of his return in future seasons -- was met with an outcry of disapproval and anger from many "Hearties" (the self-appointed term for the show's devoted fans) who felt betrayed by the plot twist.
Wagner said he knows how being the target of that kind of outrage can feel. On General Hospital, Wagner starred as Frisco Jones, who was one half of a soap opera super-couple with Felicity Jones -- played by the actor's then-wife, Kristina Wagner. His departure from the show marked the end of their on-screen relationship, and fans were not pleased.
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Wagner said that he gave Lissing some advice on how to weather the storm of the fandom's anger, and how to land on your feet.
"I wound up going to Melrose Place right around [that time], so things happened for me. And then I went back to a soap opera, to The Bold and the Beautiful, in the year 2003. So you gotta drop your ego as an actor," Wagner shared. "It's a learning and growing process for all actors to downsize your ego and upgrade your talent. That's the goal."
"Erin and Lori and Daniel all got on Facetime and Facebook and Instagram and did a real cleansing, " Wagner recalled. "I think we all expected [the strong reactions], it had to happen. But listen, [the fans] are ready to evolve too. [And] again, if you lose one actor the whole show is not gone."
In fact, Wagner feels that the upcoming sixth season is going to take When Calls the Heart in a bold, exciting new direction and that the series is "going to go to the next level."
"This is gonna be a real evolution of a television show," he explained. "I think series in the past that have lost a lead actor have had to evolve so this isn't a first at all."
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"We're all committed to this… it's going to be groundbreaking for this show, he continued. "I really look forward to it because I think it's a challenging thing for the actors, I think it's a challenging thing for the producers, writers and Hallmark in general to keep this audience interested and [to figure out], 'How do we create a really rock solid show that evolves?'"
While Elizabeth was left a widow during the show's recent season finale, there was a surprising silver lining around the dark cloud of her grief when it was revealed in the episode's final moments that she's pregnant with Jack's baby.
Now, the wealth of possibilities for Elizabeth's journey in the coming season are endless, and Wagner gave a few hints at what viewers can expect to see.
"I think there has to be suitors, I think the audience wants that. [Also], we're going to have to see a little of how Abigail, Lori Loughlin's character, rubs off on Elizabeth," he said. "They're so close, and very strong women, so it'll be nice to see how that plays out."