"I think he'd be pissed at the guard that he left on duty when he slammed the gate — shut and locked," Gilliam said during an appearance at Walker Stalker New Jersey Saturday.
Gilliam passed the buck to the Alexandrian guard who was on hand to free Negan of his restraints, pointing out that guard was on duty "when Gabriel slammed the cell door, locked," and "was in charge of making sure that Negan didn't get out."
Gabriel was upset and distracted after learning girlfriend Rosita (Christian Serratos) was wounded and in unknown condition at the Hilltop. Gilliam was adamant Gabriel "slammed the f—ing gate shut and it locked."
"And there was a f—ing guard standing by," Gilliam said, feigning an attitude. "Next f—ing question!"
Now freed from his almost eight-year jail sentence, Negan will next poke around the Grimes household before taking full advantage of his freedom while Alexandrian leader Michonne (Danai Gurira) and Daryl (Norman Reedus) deal with the immediate threat of the Whisperers, deprived survivors disguised in the skins of walkers.
"We'll see what happens now that Negan is out of his cell," showrunner Angela Kang told THR of Negan's post-prison trajectory.
"Jeffrey Dean Morgan has been cooped up in a cell all season, and even though he's doing an amazing job in there, we're going to get to see him out and about in the world. We'll see the start of a larger story for Negan as a result of that."
Creator Robert Kirkman noted on live aftershow Talking Dead Negan's freedom will head a different direction from a similar plot point that played out in his comic books, while Kang told ComicBook.com she's excited to continue to unfold layers behind Morgan's "complicated" former Savior leader.
"We've also seen that he was at the lowest of the low point earlier in the season, was suicidal. We've also seen that he has a particular relationship with Judith Grimes [Cailey Fleming] that seems like pretty friendly and nice," Kang said.
"And so, all of these things are kind of churning within Negan, and that's part of his story going forward. So I think that there's some interesting twists and turns to be had with Negan one way or the other."
The Walking Dead returns with its back eight of Season Nine Sunday, February 10 at 9/8c on AMC.0comments