The 40-year-old, who plays hotshot pilot Poe Dameron, revealed that the latest instalment of the sci-fi saga will continue to explore his character's bond with General Leia Organa through scrapped scenes he shot with the late actress.
Director J.J. Abrams confirmed that he planned to use the footage to conclude Leia's story after Fisher died unexpectedly in December 2016.
In a new interview with Sirius XM Insight's John Fugelsang, Isaac revealed that the link between the characters is a part of the new story in "Episode IX".
And the "Triple Frontier" actor said he understood why Abrams wanted to focus on that storyline.
"I wasn't surprised because I remember we were doing that, we worked a lot," Isaac explained. "(Fisher) and I worked together so much. We would talk about the scenes, and we got very tight during the shooting of that."
"So it was a beautiful thing to see, and it gets carried over into the new film as well," he added.
Resurrecting old scenes for a new film is rare, but Isaac said he hopes it will give Star Wars fans closure, and will do justice to Fisher's iconic character.
"It was definitely an unusual thing, but I also think it was right to engage with her character, and not just let it be something that fades away," he said, adding that the highly-anticipated movie will give Fisher and Leia “a proper place of honour."
While on #TellMeJohn yesterday, @netflix 'Triple Frontier' actor & @starwars star Oscar Isaac spoke to @JohnFugelsang about the effects parenting has had on his craft & the joys of working with the late Carrie Fisher— SiriusXM Insight 🔊 (@SXMInsight) 12 March 2019
📻FULL EPISODE: @SiriusXM OnDemand pic.twitter.com/vyeAZTlcUx
"Star Wars Episode IX" will beginning hitting movie screens on 19 December.