You've surely seen the innuendo-laced "Deadpool" ads, like the poster that's zoomed in on a gun right by his crotch, reading "Wait 'til you get a load of me." Well, no one can accuse Deadpool of firing prematurely.

The film, out today in theaters and already a box office success, has been in development for about sixteen years. That's right -- before the first "X-Men" movie was released, there was serious talk of bringing Marvel Comics' Merc with a Mouth, created by Rob Liefeld and Fabian Nicieza and first introduced in 1991's "New Mutants" #98, to the big screen.

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Let's start this journey in the faraway year of 2000, years before the inception of Marvel Studios, in an era where the rights to Marvel's roster of heroes and villains were licensed out to various studios, in order to develop films that mostly never got made -- and that's where "Deadpool's" Hollywood adventure story starts.

Marvel/Artisan Entertainment Deal



Starting with 2008's original "Iron Man" film, Marvel has devloped movies in-house as part of its massively successful Marvel Cinematic Universe. But before that, deals were made for the live-action rights to characters with multiple studios around Hollywood. In fact, some of these deals still remain in place today, which is why 21st Century Fox has the rights to the Fantastic Four and X-Men characters (including Deadpool), while Sony controls Spider-Man (though Sony's sharing Spidey with Marvel Studios as the result of a highly publicized deal made a year ago).

In May 2000, an ambitious deal was announced between Marvel Enterprises and Artisan Entertainment, to "turn at least 15 Marvel superhero franchises into live-action features, TV series, direct-to-video films and internet projects," as reported at the time by Variety. It's fascinating to look back at the piece now -- a "Captain America" film and "Thor" television series were both planned, but neither were brought to live-action life until more than a decade later, after the rights reverted to Marvel. Also on that list were a number of relatively obscure properties -- "Morbius," "Longshot," "Power Pack" and, most astonishingly, "Mort the Dead Teenager" -- plus "Deadpool."

At that point, Deadpool was ripe for big-screen adaptation The character was hot with comics fans, fresh off the acclaimed Joe Kelly-written run of the first "Deadpool" ongoing series, which fleshed out the character into a true solo star. Here's how "Deadpool" was described by Variety at the time: "a mercenary uglified by an experimental cancer cure who becomes a hitman taking on the hardest jobs without a care whether he lives or dies."

Of course, like so many characters that got optioned in that era, a Marvel/Artisan "Deadpool" movie never happened -- in fact, very little came of that entire deal. Artisan was purchased by Lionsgate in 2003, and the only Marvel-based films released by Artisan were the 2004 "Punisher" and the 2005 "Man-Thing" TV movie.

David Goyer's Deadpool



As strange as it seems that it took "Deadpool" 16 years to get made, it's even stranger that Ryan Reynolds has been attached for 12 of those years. At a panel at Wizard World Los Angeles in 2005, Reynolds told the crowd, "it's like that's the reason I stepped out of my mother, to play [Deadpool]."

After filming 2004's Marvel-based "Blade: Trinity," comic book movie mainstay David S. Goyer -- who wrote and directed the third "Blade" film -- was quoted by IGN in February 2004 as wanting to work with Reynolds on a "Deadpool" movie.

"I want to do something else with Ryan Reynolds because I really loved working with him and New Line wants to do something else with Ryan Reynolds," Goyer is quoted as saying at the time. "Marvel wants to do something with Ryan because there aren't a lot of actors anymore that can do credible action and be funny and that are also good actors."

The slow-burn association of Reynolds and Deadpool was even immortalized in a comic book. 2004's "Cable & Deadpool" #2 by Nicieza and Mark Brooks featured a joke where Deadpool comments that he looks like "Ryan Reynolds crossed with a shar-pei."

Of course, a Goyer-helmed "Deadpool" didn't happen, and the writer/director shifted his focus to the DC Comics side of the film world -- from "Batman Begins" to next month's "Batman v Superman: Dawn of Justice"

"X-Men Origins: Wolverine"



The bumpy ride it took to get Ryan Reynolds to play Deadpool in a movie is further complicated by the fact that Ryan Reynolds has already played Deadpool in a movie. Kind of.

Reynolds appeared in 2009's "X-Men Origins: Wolverine" as Wade Wilson/Deadpool, a character who, before his Weapon X transformation, is actually quite similar to the Wade Wilson comic book fans know and love -- wisecracking and a bit unhinged. After he becomes a superpowered villain, the poorly received film departs wildly from the source material, both visually -- no red and black costume in sight -- and in terms of his powers, with the character given the ability to absorb others' powers and also arm-blades analogous to Wolverine's claws.

But the most puzzling divergence is that after Wade became Deadpool in "X-Men Origins," his mouth was sewn shut, and the character became mute -- yes, the antihero who became a cult-favorite as the Merc with a Mouth literally had no mouth, a first-ballot candidate for the Hall of Fame of Bad Comic Book Movie Decisions. The X-Men franchise rebounded in 2011 with "X-Men: First Class," but it seemed unlikely Reynolds would get a second chance to play the character.

Test Footage Leak



Luckily, Fox didn't give up on "Deadpool." X-Men franchise producer Lauren Shuler Donner declared in 2011 that a "total reboot" of the character was in motion, one that would either ignore "X-Men Origins: Wolverine" "or mock it." (Spoiler alert, it's the latter.)

Reynolds remained attached to star, and screenwriters Rhett Reese and Paul Wernick were hired in 2010 to pen the script, following the success of their 2009 horror-comedy "Zombieland." In 2011, special effects expert Tim Miller was hired to direct, as his first feature.

Then, things stalled. Once again, it looked like a proper "Deadpool" film would never happen. Until July 2014, when test footage filmed in 2012 leaked online, showing the world what a "Deadpool" movie done right might look like, and sharing pretty much the exact same tone as the film that's now out in theaters. Fan response was very positive, and Reynolds himself has credited the leak for helping the film get actually made. Recently, the star has coyly joked that he might actually be responsible for the leak, though he officially still denies it.

R-Rated Reality



In September 2014, 20th Century Fox finally announced a release date for "Deadpool" of Feb. 12, 2016 -- hey, that's today! -- and, clearly, the movie did not shift from there. Miller remained on board as director with Reynolds as the lead, with a script by Reese and Wernick, who have said they've written a different revision each year between 2010 and now. The movie was later confirmed to have an R-rating -- relatively rare for comic book-based adaptation -- and subsequent trailers proved that the movie's language and violence definitely earned that MPAA classification.

After 16 years, "Deadpool" is now in theaters. It's received mostly positive reviews, broke a box office record, and a sequel is already in the works. Hard work pays off, and the filmmakers were clearly playing the long game. (Yes, you can read both of those statements as "Deadpool"-style double entendres.)