"Look, that one that we're talking about, that you brought up, I would like very much to make come true," Morgan told Screen Rant in the fall during a Walking Dead set visit when asked about Negan's shared scenes with the Whisperers.
"I love all the stuff with Beta and, as you know, we've added a couple amazing characters to this cast. I hope to god that Negan makes it to those scenes and that we decide that that's not going to be a part of the comic we don't do, y'know? There's been that. I've looked forward to some storylines and then they haven't come to pass."
In the comics, Negan bands with the territorial Whisperers after being freed from the Alexandrian prison. The foul-mouthed Negan quickly clashes with Whisperer second-in-command Beta but comes to respect leader Alpha, despite openly disagreeing with their barbaric way of life.
Negan later betrays the Whisperers to earn the trust of Rick Grimes as part of his growing rehabilitation, and is recruited to the front lines in the Whisperer war. It's there Negan emerges as Beta's chief rival before going on to win his freedom — and a new start.
"I hope that those happen because as a fan of the comic I think they were very important moments. And as a fan of this character, I think they're very important for the Negan storyline," Morgan said.
"If Negan's storyline is just what we've seen so far, I'd be very disappointed because I think there's so much more to this character."
Morgan admitted last year he'll be "forever disappointed" the Carl-Negan dynamic couldn't play out as it did in the books following the Season Eight death of Carl Grimes (Chandler Riggs). He's since established a comparable relationship with Carl's half-sister Judith (Cailey Fleming).
Sunday's mid-season premiere revealed Alpha, portrayed by Samantha Morton, and daughter Lydia (Cassady McClincy). Beta will debut in the coming episodes, played by Morgan's friend and former Sons of Anarchy star Ryan Hurst.
The Walking Dead Season Nine premieres new episodes Sundays at 9/8c on AMC.