Today, a Marvel movie is a surefire hit -- but that wasn't always the case. From James Cameron's Spider-Man to George Clooney playing Nick Fury, many Marvel movie ideas never made it to screens.
Though "Captain America" leaped from comics to the movie theatre all the way back in 1944, it was more than 40 years until Marvel's next big screen outing. During that time, Marvel figurehead Stan Lee left behind the comics he had made his name writing to make a full-time job of shopping the company's characters to TV and movie producers.
The delightful "Marvel Comics: The Untold Story" by Sean Howe details how in the 1970s, '80s and '90s stars from Tom Selleck, Brigitte Nielsen and Carl Weathers to George Clooney and Leonardo DiCaprio came close to donning the capes and tights of Marvel's heroes. Click through our gallery to see what those movies could have looked like, and try and tell us they wouldn't all have been amazing:
So why did none of these potential movies make it?
Sometimes the filmmakers simply didn't understand what they had. Production company Cannon films at one point worked on a draft of a script about Spider-Man in which our friendly neighbourhood wall-crawler literally turned into a tarantula.
Then there's the legal issues. The history of Marvel is a tangle of legal rights for films, toys and other spin-offs being farmed out to other companies -- frequently followed by decades spent trying to claw them back.
The rights to Spider-Man were a tangled web for decades until Spidey finally became part of the Marvel cinematic universe in time for this year's "Civil War". Aquatic antihero Namor the Sub-Mariner is less fortunate, still drowning in rights issues and conspicuous by his absence on the big screen.
Probably the most notorious -- and hilarious -- example of a tussle over rights is the "Fantastic Four" flick filmed by legendary B-movie producer Roger Corman. He threw the film together on a shoestring so his rights wouldn't expire -- only for Marvel to take one look and throw money at the producers to bury the infamously shoddy affair:
Meanwhile some projects simply ran out of time. We're big fans of the "Daredevil" TV show on Netflix, but sadly, it put the kibosh on an intriguing 1970s-set proposal by "Narc" and "Smokin' Aces" director Joe Carnahan when Fox held the rights to the horned hero. The project fizzled when the rights reverted back to Marvel in 2012, but we can see what might have been in Carnahan's sizzle reel of atmospheric clips from classic '70s crime and blaxploitation movies.
And of course, many of these projects were conceived before 1989's "Batman" proved how much of a box office sensation a superhero could be. They were also in the works long before CGI helped special effects catch up with the characters' special powers.
But even now, with Avengers team-ups and solo movies alike smashing the box office, and a long list of titles bound for theatres, there are still a number of other projects stuck in limbo.
Toddler team-up "Power Pack", martial arts mash-up "Shang-Chi" and supervillain-offspring drama "Runaways" have all been announced by Marvel but are yet to go ahead. Just recently, "Inhumans", which looked like it was all set for release in a couple of years, was struck off the slate.
Still, there's plenty more where they came from, true believers. So let's salute the Marvel movies that never were, safe in the knowledge that there won't be a shortage of superhero showstoppers anytime soon.