Viking's youngest brood of Lothbroks will never look at their father the same way again.

Bjorn's (Alexander Ludwig) keen eyes keyed him in to Ragnar's (Travis Fimmel) calamitous downward spiral back in season 3. His half-brothers, Ubbe (Cormac Melia) and Hvitserk (Stephen Rockett), we're a bit slower on the uptake, but, now that the youngsters have seen the storied warrior and ambitious king brutally kill an innocent woman, Aslaug's (Alyssa Sutherland) sons have a whole new outlook.

If Michael Hirst's original script had gone to film, however, the tiny Norsemen would have had to learn about their father's treachery in an entirely different way. According to Dianne Doan, Yidu was initially slated for a battlefield death.

"In earlier drafts - I might get in trouble for saying this - I died differently. It was a battle scene. I was prepared. I was so excited to be able to fight. But with revisions and rewrites came this scene. And part of me was so upset." Doan told Entertainment Weekly of Yidu's watery demise. "Because you're right. It was so personal, for him to do that. From what I remember, we've never seen him outright kill a... well, it doesn't matter if it's a woman, but someone with that sense of brutality."

The rewrite, however, had the benefit of turning characters and viewers against a now morally gray Ragnar. Will this moment prove to be another domino in Ragnar's ultimate downfall?

"Ragnar is always painted as a hero, these past four seasons," Doan explained. "I told [Fimmel], 'The audience is gonna hate you.' He looked at me, he's like: 'I think you're right. This is the exciting part.'"

Find out more when "Death All Around" picks up in the wake of Yidu's death. Vikings airs Thursdays at 10 p.m. ET on the History Channel. Click the video below to see a preview for tomorrow's episode.

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