A group of heroes published by
Marvel Comics. The
Fantastic Four first appeared in
Fantastic Four #1 in 1961 and were created by
Stan Lee and
Jack Kirby.
When you talk about the original super-heroes of the Marvel Universe and one of the Lee and Kirby's most enduring creations, you are talking about the Fantastic Four. Born of a desire to reintroduce super-heroes into the comic book industry and the lack of the Marvel publishing house having any on-going characters, Stan Lee and Jack Kirby created a group that was more family than team.
Reed Richards, a brilliant scientist, designed and built a spaceship, but had been denied permission to test it. Enlisting the help of his college roommate and test pilot Ben Grimm, his girlfriend Susan Storm, and her kid brother Johnny Storm, Richards broke into the launch site where the rocket was kept and tried out his new rocket. There has since been an obvious tightening in security around NASA sites and the responsible people have been sacked. The test went well, until the rocket passed through a cosmic storm exposing the crew to high doses of cosmic radiation. Rather than developing festering boils, hair loss, internal bleeding and death, the radiation had a mutagenic effect upon the crew. The ship crashed and the quartet began to demonstrate amazing new powers: Richards could stretch the various parts of his body, Ms. Storm had the ability to turn invisible (and later create invisible force fields but that was not mentioned initially), Johnny Storm could burst into flame in a good way and fly around and project fire, and poor Grimm was gained super-human strength and invulnerability, but ended up looking like he was covered in orange stucco. The group decided to use their new powers to help the world as the Fantastic Four and so took up the code names: Mr. Fantastic, Invisible Girl, the Human Torch, and the Thing.
From the beginning, the Fantastic Four were different from other heroes. First, they did not wear masks. They publically revealed their identities. This ended up being problematic when the Storm's father was used as a pawn in one of their enemy's evil schemes, but you have to take the good with the bad. Also, everyone knew where they lived. They became sort of celebrities.
Their list of enemies grew pretty quickly. They fought the Mole Man on their first outing and have faced him many times since. They have also battled the likes of Annihilus, Blaastar, the Frightful Four, the Puppet Master, the Skrulls, Ronan the Accuser and others. Probably their two most famous enemies have to be Victor Von Doom, otherwise known as Doctor Doom, a former associate of Reed Richards who blames him for an accident that scarred his face and so wears a metal mask. Doom is the on-again, off-again ruler of a Eastern European country known as Latveria. There other most famous opponent is the world-eating giant known as Galactus.
The Fantastic Four have had many adventures over the years, too numerous to outline here. Reed Richards and Sue Storm got married, setting the standard for nearly every super-hero wedding from then on (i.e. villains have to crash it and there has to be a really big battle). The couple has had a son Franklin who had incredible reality changing powers. Grimm has over the years gone from looking like a pile of Play-Doh to looking like he was covered with bricks, to back to the molten look, to being able to control his transformations, to being trapped forever in his form as the Thing, to transforming back into plain old Ben Grimm and wearing an exo-skeleton to be the Thing (making the stage before sort of silly), to being exposed to another dose of radiation and being like the uber-Thing, etc. The Human Torch has been a punk in a blue costume, a punk in a red costume, a punk in a red costume who gave Spider-Man a hard time, a punk in a blue costume again, a slightly less annoying punk who was married to the Thing's old girlfriend, to a slightly more annoying punk who was married to a Skrull who posed as the Thing's old girlfriend, etc. Needless to say, 40+ years of story telling, the Fantastic Four have gone through many different changes.
Despite the group's usually being recognized as these four individuals, others have been members for a short time. The first replacement was when the Invisible Woman was pregnant and the Inhuman known as Crystal took her place in the group when she wasn't slapping the Human Torch's face. Her sister, Medusa, also served in the Invisible Girl's place for a time. The 1970's saw a brief time when Luke Cage took the the Thing's place for a time, but this soon ended when it was realized that Reed had no idea what Cage's street lingo meant. This is probably one of the most ludicrous moments in the group's history as they are about as white bread as you can get, making Cage's inclusion sort of like if they had decided to punch up the Brady Bunch with Jim Brown instead of cousin Oliver.
Later the group saw other changes to its line up. After the Secret Wars, the Thing was replaced for an extended time by She-Hulk. Still later, the group saw the Richards spend an extended time away from the team in an attempt to have a "normal life" and under the leadership of Grimm, the team included Crystal again and a woman named Ms. Marvel, but not the blonde one, a red-head who eventually ended up looking like the Thing with breasts. Later the team had the second version of Ant-Man as a member as well.
The Fantastic Four has also had some pretty interesting supporting characters over the years. These include such notables as Willie Lumpkin, the Fantastic Four's ear wiggling postman. They have also had a God's honest witch as Franklin's nanny for some inexplicable reason in the form of Agatha Harkness. As well, they have had on retainer for quite a while Wyatt Wingfoot, a Native American with lots of muscles and apparently a lot of free time.
The Fantastic Four have been based in the same location, but in two different buildings over the years. They initially lived in the upper floors of the Baxter Building. This housed their living quarters, Richard's labs, a launch site for their vehicles the Fantasti-Car and the Pogo-Plane, the entrance to the Negative Zone, as well as other wonders that Richards created over the years. The building was picked up and pulled into space twice by the plans of Doctor Doom, the first time to be replaced exactly where it was left with no seeming damage to the support structure, and the second time it was destroyed in a massive explosion. Rather than rebuild the Baxter Building,Richards had constructed Freedom Four Plaza at one has to imagine were considerably higher insurance rates.
The Fantastic Four have had a couple of cartoon series, including one in the 1970's in which the Human Torch was replaced by a robot named HERBIE. The group has also been the subject of a Roger Corman film that has seen close to no distribution.