But the actor is confident he'll be back for the potential third film in the franchise, and he thinks that his co-star Jeff Bridges will be along for the ride.
ComicBook.com spoke with the actors ahead of the premiere, where they revealed their hopes to reprise the roles of Harry Hart and Agent Champagne for Kingsman 3. Check out the clip above!
"We're working on it," said Bridges. "Between interviews, we're jamming on ideas. There's no script but Matthew [Vaughn]'s been talking about it from the beginning! You said he's always envisioned it as a trilogy," he said, referring to Firth.
"I remember very early conversations with Matthew," said Firth. "He felt that three [movies] would be right for this. He hadn't got them mapped out, I just think he could feel three."
But a third movie has yet to be greenlit at this point. It all depends on the success of Kingsman: The Golden Circle.
"Each one, of course, depends on people going to see them," Firth said. "If this movie doesn't work out, that's it. So, everybody go and see it, and we'll definitely, I think- definitely is a big word, but I think we'll do it."
Given the buzz building around the film, it's a safe bet that it will do as well as Kingsman: The Secret Service, if not better.
And with all of the plot threads set up for payoffs down the road, Vaughn probably has a decent idea of what he wants the last movie of the trilogy to accomplish, script or no script.
Of course everything can change over the next few months, but the buzz surrounding the second movie in this franchise is pretty strong.
We'll find out after Kingsman: The Golden Circle premieres in theaters this Friday.
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