Cole Sprouse, KJ Apa, and Lili Reinhart Talk Tonight's Heartbreaking 'Riverdale' Scene

Spoilers ahead for "When A Stranger Calls," tonight's episode of Riverdale.

Tonight's episode of Riverdale featured the breakup of one of the show's fan-favorite relationships.

During the episode, Betty Cooper was being called periodically by someone claiming to be the Black Hood, the killer stalking Riverdale. He instructed her to break off her friendship with Veronica Lodge and her relationship with Jughead Jones, threatening the lives of Betty's family and loved ones if she did not comply.

"It is quite devastating. It is, and it is sad and heartbreaking to see her have to do that," said Lili Reinhart, who plays Betty. "You know it is to protect him, and she does all these things to protect them. And they don't know and the audience knows and that is what is so hard to see about it and she is trying to do the right thing. And you know Veronica and Kevin are hating her for it and Jughead is confused. It is sad because you want to tell them she is not doing it on purpose. As for Betty and Jughead at the end of 205, you hope that there is a chance that Betty can have in the future to explain herself and to reconcile with him, but with the Black Hood still being a present figure in her life, it is hard to imagine that her relationship with anyone can continue or go back to the way that it was."

Ultimately, she decided she had to comply — but she could not bring herself to break things off with Jughead herself, and instead sent Archie Andrews to do it. When Archie saw Jughead taking part in Southside Serpents initiation rites, he lost his cool and told Jughead in a not-too-friendly way that Betty was done with him.

"I think at the time, it was a really hard time for him to do — to approach his best friend and tell him that," said KJ Apa, who plays Archie. "But obviously it was for Jughead's own good. The only reason why he did that is because they're best friends and he had to do it in order to protect Jughead."

While Jughead is likely to be hurt by Archie's delivery, actor Cole Sprouse, who plays the character, says the breakup itself is not exactly a surprise.

"There's that one line in it, too, that he goes, 'No, you guys haven't been good,' and he's trying to lie to himself and he goes, 'No, I saw her earlier!'" Sprouse said. "But he knows he's on the Southside now, and he knows he's been away from everyone, and I think also Jughead has absolutely no problem seeing himself as someone who could be easily thrown to the wayside, so I think something like that probably affects him a little bit. But he's also got his boys behind him, so it's not like he's going to be like, 'NO!' The way that scene was shot was kind of funny to me, watching it back. I think Archie is also Jughead's weakness when it comes to Betty, because they were kind of the three amigos when they were young, but Betty had always favored Archie and it's something that will definitely see prevalence later on in the season, and just how much of a friendship Betty and Jughead had, even though it was just the three of them when they were younger or if Jughead felt more like a third wheel. So Archie coming to deliver the bad news is not only a slap from Betty, but really a slap from Archie too, which I think is something we explore a lot later."

Riverdale airs Wednesday nights at 8 p.m. ET/PT on The CW.