When I first started doing comic book research many years ago, I focused primarily on the Fantastic Four. It was my favorite comic by far, and I found the more I knew about its creation, the more I appreciated the book itself.
One of the theories I had was that creators Stan Lee and Jack Kirby were influenced in creating the FF by movies of the time, and I went through watching a number of movies that were made from 1959 through early 1961. I even tracked down actual release dates to see which movies would have been in the theater around the time the FF was being created -- probably around April or May 1961!
I pretty well kicked my theory out the window, as I wasn't finding much in the way of direct inspiration. The closest movies I could really get were The Lost World featuring Michael Rennie and Claude Rains, and The Angry Red Planet starring Gerald Mohr and Les Tremayne. As I'm largely taking today off, I opted to re-watch both of them.
The Lost World is (very) loosely based on the Sir Arthur Conan Doyle novel of the same name. Professor Challenger claims he discovered a remote land where dinosaurs still exist, and he takes an expedition down to prove it. Though the group in the movie consists of eight members -- obviously more than either the original novel or the FF that I thought might take cues from -- there are too many characters for the writers here to adequately handle. Professor Summerlee and Costa are entirely superfluous to the journey, and the Holmes siblings do very little to advance the story either. Perhaps most striking about the movie -- as it pertains to a possible influence on Lee and Kirby -- is that love interest Jennifer Holmes follows along mostly to be with John Roxton, and David Holmes comes along because... well, he's Jennifer's kid brother. David is also the smooth-talker of the group, managing to successfully woo a native girl despite a language barrier.
The Angry Red Planet is about a group of four "scientists" that are the first humans to visit Mars, and run into a few scrapes before returning to Earth. They're called "scientists" in the movie, but they're more 1950s-style adventurers; their casual disregard for scientific examination or analysis of anything throughout the whole movie is almost hilarious. They do have more of a physical template for the FF, though: three men, one woman. One of the guys is bruiser type from Brooklyn, another is grey-templed hero. There's not a direct parallel, by any means, but some of the same general themes are prevalent in the early issue of Fantastic Four.
As I said, I dropped my theory as these types of connections are, at best, tenuous. But it is interesting, I think, to help get a feel for where the U.S. was as a society at large. There were all these discoveries and advancements going on, which most people didn't really understand. Science was, for the average Joe, just another big adventure that could wrestled and hog-tied like the Old West. Just charge on in, and you could just figure it out as you went along. Actually, a lot of America's psyche flows from that mindset to this day. We remain a nation playing at "cowboys and injuns". But it's interesting to see that application of science hold true in our fictions, regardless of whether we're sending someone to Mars or tracking through the jungles of the Amazon looking for dinosaurs. I think that was really the big take-away for me.
On a curious side-note, three of the main actors from ARP later went on to take roles in comic-related properties. Gerald Mohr became the voice of Mr. Fantastic (1967 Fantastic Four cartoon) and Green Lantern (1968 Aquaman cartoon). Jack Kruschen played Eivol Ekdol (1966 Batman) and Captain Keene (1994 Lois & Clark). Les Tremayne played Mentor in the 1970's Shazam! show, as well as lending his voice to Ultraman: The Adventure Begins, Challenge of the GoBots and The Pirates of Dark Water among a host of other Saturday morning favorites. Jill St. John, from Lost World, also appeared in Batman and later took the title role in the 1976 Brenda Starr movie. For completeness' sake, I have to point out that Reinne, too, appeared in Batman.