Kingsman: The Golden Circle opened in movie theaters last weekend and Mark Millar couldn't be happier. The sequel to Kingsman: The Secret Service - based on his and Dave Gibbons' 2012 comic book series - knocked It: Chapter One from the box office top spot, with a debut of $39 million, narrowly beating the original film's opening weekend tally of $36.2 million. It seems Mark's trust was well placed with director/co-writer Matthew Vaughn when, after getting drunk at a pub, they decided to bring his idea for a fun spy movie to life - but the pair already had a history of success to build on.

Mark's Kick-Ass comic book series marked the first collaboration with Matthew and the resulting movie adaptation was both a critical and commercial hit in 2010. Two years later, Vaughn gave up the opportunity to direct X-Men: Days of Future Past (the sequel to his X-Men: First Class) to direct the first Kingsman film which began development the same year that Millar released the original book. He left the director and Kick-Ass screenwriter Jane Goldman to co-write the script and came onboard as an executive producer. A role he tells Screen Rant he much prefers.

"Exec producer is actually a perfect job on a film because it’s all the fun with none of the stress. It means different things on different movies; something like Kick-Ass or Kingsman: The Secret Service meant I watched all the auction recordings on my computer, saw all the character designs, read drafts of the script and so on, plus sat in edits every Wednesday for a couple of months."

His and Vaughn's teamwork paid off as the final product grossed $414.4 million worldwide against a $94 million budget. Both critics and audiences praised the subversive spy film which introduced Gary "Eggsy" Unwin (Taron Egerton) as the rude boy thief turned gentleman spy who, with the help of his Kingsman mentor Harry Hart (Colin Firth), undertook the mission of saving the world. It seemed obvious then that a sequel would be in the works and just over four months later 20th Century Fox confirmed the news, however, Mark took a step back in his role both in the franchise and comic book series, entrusting them both to others.

Kingsman The Secret Service

"I wrote the original book, of course, back in 2011 and we published in 2012, but I’ve never returned to the franchise," Mark explains. "I planned to at some point and had ideas for several books, but to be honest the success of the first movie kind of caught me off-guard and I’d already committed to six new comic-book franchises with six different artists and I didn’t have time to get involved."

This led to him hiring Rob Williams and artist Simon Fraser to pen the second Kingsman book, The Red Diamond released this year, and leaving Vaughn and Goldman to come up with their own original story for The Golden Circle while he prepared for the sale of his comic book publishing house to Netflix.

"I was busy preparing Millarworld for the Netflix sale while the movie was being made too so I kind of came to the party much later as a producer," Mark recalls. "I was much less involved and I mainly spoke to the guys after the film was cut when we were looking at little edits and tweaks. I talk to Matthew on the phone almost every day and have done for the last ten years, but we spend 90% of the time gossiping and it’s not hard work by any stretch of the imagination."

Mark has taken a massive step back from the franchise now he's working with Netflix full time

The sequel has received more mixed reviews than the original (read our review here) but Mark stands by it, and praises not just the Elton John cameo but the way Matthew presents the heavy violence on screen. "I love this movie, but mainly as a viewer," he explains. "Movie violence? I love it. Violence in real-life, not so much. But the violence in Matthew’s movies is operatic. He does it better than anyone."

So what does the future hold for the Kingsman franchise? Vaughn has promised a third movie and revealed some details about what he wants to see, and Millar continues to entrust his friend with its cinematic future now that he has more pressing commitments elsewhere. "I’m full-time at Netflix now and not involved in the third Kingsman at all beyond co-ownership, but I’m completely relaxed about it because Matthew and Jane are so brilliant," the comic book writer enthuses. "It’s a bit like being Jor-El and firing your baby off into space, but knowing the Kents are going to raise him better than you would. It’s perfect."

Though it seems even Mark is clueless about what to expect in Kingsman 3. Apparently, Vaughn "mentioned a couple of very early ideas over a bottle of whiskey" a few months ago and Millar has managed to forget them all. "I honestly can’t remember," he admits, "but Matthew and Jane did a great original story here and I have no doubt they’ll do an even better one for number three."

NEXT: Taron Egerton Wants Dwayne Johnson to Join Kingsman 3

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