Treyarch has revealed that it started work on Black Ops 2 before development had been completed on the original Black Ops.
"That's how much we wanted to do [Black Ops 2]," game director Dave Anthony told the Metro.
"And that was a decision that David Goyer and I made because David came in with about three months to go on Black Ops I and we had a great working relationship and we were just so excited to get going on something."
Anthony says that he "knew" Treyarch had to continue telling the story of Woods and Mason, even before the studio knew how well Black Ops would be received.
"And we knew that the story of the characters from Black Ops 1 hadn't finished," he continued, "and we knew that when we were writing Black Ops 1, we knew we were going to continue something. Or we wanted to at least."
"And it was interesting, we'd just submitted to the first parties for Black Ops 1, and we were trying to figure out already the branching story elements for Black Ops 2, because the way the branching story works it really restricts what you can change once you commit to it. Because if you change one element it has ramifications on everything."
Anthony says that most of his initial ideas made it into the final game.
"So almost two years ago to the day we had a very clear idea what the story was going to be, what the character arcs were going to be, and what the plot points were going to be.
"Some things evolved over time but what we actually conceived over two years ago is very, very close to what it actually is."
Call of Duty: Black Ops 2 released on Xbox 360, PlayStation 3 and PC yesterday, with approximately 2,000 stores across the country opening at midnight to celebrate its release.
But could Black Ops 3 already be in development...?