Deadpool did not become one of the most popular comic book characters of the last 30 years because he has a particularly interesting backstory or physical aesthetic — those were more or less ripoffs of the DC assassin character Deathstroke, as creators Rob Liefeld and Fabian Nicieza will openly admit. No, the reason that the semi-invincible and very ugly assassin has become such a beloved fan favorite — and monster box-office juggernaut — is that Wade Wilson is a lot like comic book readers: irreverent, sh**-talking, and obsessed with pop culture.

There has never been a tedious panel in a Deadpool comic book. Each moment is injected with extreme acts of violence and/or silliness, an unceasing assault of flippancy, sarcasm, innuendo, riffing, and out-of-left-field cultural callbacks. Because he so often breaks the fourth wall, it can be easy to forget that there are writers who put those words into the Merc With a Mouth's indefatigable yapper, and that the singular voice of the character has been crafted over years by a procession of gifted creators.

Deadpool is somewhat unique in the twisted world of comic books in that his storylines take a backseat to his jokes, so SYFY WIRE spoke with some of the most prominent and long-running writers of Wade Wilson books to learn just how to craft the perfect Deadpool joke.

Joe Kelly was the first writer on the first monthly Deadpool book, and during his 33-issue (plus several annuals and one-shots) run, he set what would become a somewhat definitive tone for the character. A lifelong comics fan, he was a relatively new writer when he took over the monthly book, and pulled in some of his childhood favorites to help set the course for his work.

"I always liked the take that Spider-Man was yammering the whole time because he was actually covering being afraid," Kelly told SYFY WIRE. "Deadpool was using it to distract you and mess with your head. It was as deadly as any katana he was wielding at the time. For me, it was jamming everything in the bazooka and then shooting it out. It was that sort of Bugs Bunny, Robin Williams rapid-fire combo, with a little dash of Monty Python. It's the sort of humor that I like with all the wordplay. It's then just picking on the characters in the Marvel Universe because this is the way Deadpool interacts with the world."

From Deadpool #2 by Joe Kelly | Credit: Marvel Comics

Kelly also sought to juxtapose Wade's public flippancy with a grimmer interior world, making for darker jokes during heavier moments. Gerry Duggan, who took over the book in 2012, had his share of zany cracks and gimmicks — he's also worked as a TV comedy writer and teamed with comedian Brian Posehn at the beginning of the Deadpool run — but also pushed hard in the darker direction.

"The perfect Deadpool joke," Duggan tells SYFY WIRE, "is the one that you might feel bad about, but you can't help but laugh at." Duggan began his just-completed run on Deadpool by having the character kill the evil reanimated corpses of dead American presidents, which definitely hit that standard.

There was a time, though, when laughing wasn't the priority, and the darkness overshadowed comedy in the pages of Deadpool. Gail Simone was brought on to the series in 2002 when it was adrift from the tone that Kelly had established.

"It's hard to remember now, but Deadpool was going through a low point in his popularity," Simone tells SYFY WIRE. The last few writers had tried to make him a bit more serious and a bit less humorous, and it was felt that he had lost his original fans. So when [Marvel EIC] Joe Quesada asked me to pitch, I was brand-new to the industry, and he only gave me one instruction: He wanted Deadpool to be ‘laugh-out-loud funny' again. That was it. I hadn't really read the character at all."

Her approach: Right the ship by making the waters a lot more choppy. (Yes, we know that this will become a mixed metaphor.)

"Every issue should be a roller coaster," Simone explains. "I want you to have that moment of unexpected drama and beauty and reflection, followed by that moment where you have nervous laughter, and maybe a few points along the way where you feel like puking just a little. It can't be all cream pies in the face, that's literally my least favorite way to use the character."

One thing has been consistent: Deadpool has always spit out highly specific pop culture references; to go back and read old issues is to get a burst of nostalgia for old tabloids, TV Guides, episodes of Entertainment Tonight, and watercooler conversations. Some allusions have aged better than others, though finding quips about forgotten celebrities and flash-in-the-pan hysterias offers its own kind of delights. Even though MTV and cable made it seem like the world was living in fast forward, Kelly was actually lucky to live in a slower time for pop culture, which gave him a bigger pool of potential targets.

From Deadpool #1 by Joe Kelly | Credit: Marvel Comics

"This was pre-explosion of the internet, so it was people on the TV all the time that I found annoying or somebody you thought of in one particular role," he said, when asked about how he chose his topical humor subjects. "Maybe someone Deadpool found attractive that other people would not typically find attractive, there would be some gag like that. It was just taking anything that I touched, that people would respond to, and giving it a little bit of a tweak that they would recognize. The tough thing about the pop culture references is they get old super-fast."

Kelly's first issue of Deadpool holds up pretty well. The character makes cracks about Denny's Grand Slam Breakfast, still a staple at the chain diner, and name-drops Keanu Reeves and Sandra Bullock in a joke about the movie Speed. The movie might be unfamiliar to younger millennial readers, but the stars are certainly still A-listers.

Duggan, operating in the prime of Twitter's non-stop news churn, felt the pressure to deliver timeless jokes with every issue.

"You have to be careful about balance," he says. "Once you hit print you're never gonna come back and punch up and joke if it becomes a moment in its time. And so yeah, it's a great question. You know, I think it's something that the movies have to grapple with in the same way. I just think if it makes you laugh, that's kind of the only barometer. Then you'd have to ask yourself, hey, did I make a joke that references Sinatra or did I do a joke about someone that no one's going to remember?"

From Deadpool #4 by Gerry Duggan | Credit: Marvel Comics

That issue has been remedied in part by widening Deadpool's own frame of reference. That creates an element of mystery to the character, forcing the reader to wonder how the hell this foul-mouthed murderer is so well-read and so deeply educated, and also allows the writers to work in whatever offbeat obsessions they might be exploring at the time.

Al Ewing, who is writing a Choose Your Own Adventure-style mini-series for the character, is taking full advantage of that expanded worldliness and meta-humor. Luckily, comedy as a whole has gotten niche enough to support that very specific vision.

"One of my favorite TV shows is Archer, and one of my favorite things about it is the out-of-left-field references," he explains. "There was an extended 'Bartleby the Scrivener' riff early on that really sold me on the show as a whole — it was a funny joke about making a joke based on an esoteric reference, and then I looked up the reference and I found the joke funnier after that. This is something I wish we saw more of, the idea that you can trust the audience, and trust that what they don't know they can look up or puzzle out."

Ewing's upbringing in the UK, with its trademark mix of high-low comedy, with spit takes and silliness injected into pseudo-stuffy intellectual discourse, also has influenced this version of Deadpool's sense of humor. He cites the TV comedy The Young Ones, which he describes in a succinct manner as "a surrealist slapstick gag show with lots of jokes about bogeys and smelly socks and also jokes about the history of revolutionary communism, delivered by Alexei Sayle pretending to be a train driver," as a prime influence.

"That's very much the kind of humor I think fits with Deadpool, this dumb-but-smart anarchic play, where there's no imposed limits on the knowledge you assume the characters or the audience have and you're free to go on riffs about stuff," Ewing tells SYFY WIRE. "I feel like Deadpool — partly because Wade's been around and has presumably picked stuff up, partly because he knows he's in a comic — has the freedom as a character to have vast knowledge and use it entirely to make dumb jokes."

Given the character's popularity, which is born in part of his penchant for saying the worst possible thing at the worst possible time, Marvel is said to be largely hands-off with Deadpool writers. Ewing said the company largely only scrutinized his first book, to make sure he had the tone and structure for a choose-your-own-adventure book down right. Then he was pretty free to make the jokes he wanted, though there were a few exceptions.

"The legal department get gun-shy about song lyrics and overt likenesses, which is understandable. An appearance from Satan was changed to Mephisto. Again, understandable, because I'm from a country that's quite lackadaisical about the horned one, but I know things are different over there," Ewing says. "The only other joke I can remember being cut is a Val Doonican joke, which wasn't offensive but was totally impenetrable, relying as it did on specialist knowledge of the entertainer Val Doonican. I meant what I said about trusting the audience, but sometimes you do need someone to pull you back."

In the end, Duggan mostly relies on his gut, citing the philosophy of one of entertainment's great minds.

"It's really hard to explain what makes a good joke," he says. "One of my favorite quotes is from Roger Ebert, who said you can't talk anyone out of a laugh or a boner. It's really true."

Additional reporting by Bryan Cairns.