After being bombarded by cosmic rays on a rocket trip, Reed gains the ability to bend and stretch his body like rubber and takes the name Mr. Fantastic. The crew also gained special powers and they decide to create the Fantastic Four. They face and defeat their first enemy, the Mole Man.
He and the rest of the FF are despondent on New Year's Eve due for various reasons. Reed is still upset over Sue leaving the team and taking Franklin. Before long, however, Thundra arrives in Times Square and challenges the Thing to a fight. Johnny confronts her but she fans a clock hand at great speeds and quenches his flame. The Thing accosts her but she kidnaps Alicia Masters and postpones their fight for three days. The FF return to their headquarters. Three days later, after preparing a stadium for the fight, Reed observes as Thundra sends the Thing flying out of the stadium. The team save Ben by changing him back to human form temporarily thanks to one of Reed's machines, to which Thundra refuses to defeat a weakened Thing. Thundra releases Alicia and the team leave.
The Fantastic Four meet the Skrulls for the first time when they plan to invade Earth. The aliens take their appearances to frame them for crimes. Reed scares then away and hypnotizes those who remained on the planet so they believe they are cows.
Now living in the Baxter Building in New York City, Mr. Fantastic and the Fantastic Four stop the Miracle Man who plans to take over the world using his apparent magical powers. Mr. Fantastic helps defeat the villain whose powers were only hypnotic illusions.
Mr. Fantastic and his team make their first encounter with the Sub-Mariner who attacks them with a gigantic creature. After Namor offers to cease hostilities if Sue agrees to marry him, the Atlantean is blown away into the ocean by a vortex generated by the Human Torch.
Doctor Doom, a man whom Reed knew at college, has taken the Invisible Girl hostage to force Mr. Fantastic and the others to travel back in time on his Time Platform to retrieve Black Beard's chest, which contains the Stones of Merlin. After bringing back an empty chest, they escape and Doctor Doom flies away from his blazing castle.
Mr. Fantastic faces Doctor Doom and the Sub-Mariner who have joined forces to destroy the Fantastic Four. When Doctor Doom pulls the Baxter Building into space, sending not only the heroes but also the Sub-Mariner to their death, the team decides to work with the Atlantean and together they defeat Doctor Doom.
Reed Richards is secret working on a formula to change Ben Grimm back to normal. The Thing apparently goes mad, attacking Mr. Fantastic and the Human Torch, and during the battle, he accidentally gets in contact with the formula that temporarily turns him into Ben Grimm and puts an end to the Puppet Master's mind control over him.
Going bankrupt, the Fantastic Four accept to star in a movie to restore their financial health, unaware that it is a scheme from the Sub-Mariner to destroy them. After the boys survive the traps that he has sent them into, Namor is forced to respect his part of the deal and pay them for their participation.
Reed gives Ben his new serum to turn him back to normal and the formula seems to work. After they recall how they quickly became friends at State University and remember their military service, Ben changes again into the Thing, meaning that Reed's serum was not permanent after all.
Using their new Fantasti-Car, the Fantastic Four accompany General Ross back at his desert base to help find and stop the Hulk whom he accuses of wrecking his installations. The team confronts the Hulk for the first time and the battle takes them to a ghost town where they finally discover who is truly behind the sabotages. The Fantastic Four get their first ceremony in their honor.
Dealing with Spider-Man for the first time, the Fantastic Four take defensive measures when he breaks into their building but it turns into a battle. When he is finally given the chance, Spider-Man explains that he wants to join them but Reed informs him that they don't get paid so he leaves.
After finding a way to harness the energy of a meteorite he collected, Reed flies the Fantastic Four to the Blue Area of the Moon where they find remains of an ancient civilization. Then they are attacked by the Super-Apes and the Red Ghost. Both teams start to fight but they are interrupted the Watcher who teleports them to an isolated area of the moon where the Fantastic Four defeat the Red Ghost.
After a short separation to explore disappointing personal career opportunities, the Fantastic Four reunite. Meanwhile, the Mad Thinker has invaded their headquarters and used Reed's research notes on DNA to create a life-form that he called the Awesome Android. The Fantastic Four manage to neutralize the android and Reed outsmarts the Mad Thinker by adding an unexpected human element to his equation.
Reed gives the Thing a formula that changes him back to human form, but growing tired of being a Guinea pig, Ben asks his friend to work on a cure for Alicia's blindness instead. They use Ant-Man's serum to enter a Micro-World where Doctor Doom has imposed his tyranny. Soon joined by Ant-Man, they manage to defeat their arch-enemy and free the Micro-World people. Back in their world, the Fantastic Four track down Doctor Doom who is terrorizing the city with his evil inventions. They find their foe in his floating fortress but he chooses to escape by jumping off his hideout.
The team faces the Super-Skrull, a Skrull warrior that has been artificially enhanced to duplicate and outmatch all the powers of the Fantastic Four. The invader clearly has the upper hand against the four heroes until Reed devises a jammer that blocks the rays from the Skrulls' planet powering up the villain and the Human Torch is able to entrap the Super-Skrull inside a remote crater and seal it with an air-tight dome.
The Sub-Mariner captures the Fantastic Four to inform mankind that they will no longer be allowed to trespass the seven seas and the skies above. Later, Reed relays the message to the United Nations, emphasizing that it is a serious threat. This prompts Namor to declare war on the surface people. As the Atlantean army invades New York, Reed invents a device to evaporate the water in their enemies' helmets, forcing them to retreat back to sea.
Reed uses Doctor Doom's time travel machine to take the Fantastic Four to Ancient Egypt where they may find a cure for Alicia's blindness. They find themselves powerless and enslaved by Rama-Tut, a time traveler from the year 3000. When the team recover their senses and powers, and Rama-Tut is forced to escape in his time machine. Due to its radiation, the cure has not been transported when the heroes make it back to the present.
The Hate-Monger uses a Hate Ray to encourage violence among the citizens and turns the Fantastic Four against one another. Reed Richards gets the visit of Colonel Nick Fury, whom he has not seen since World War II. Fury came to ask for his help to stop a revolution in the Republic of San Gusto. Despite their internal feud, the Fantastic Four manage to put an end to the Hate-Monger's plans.
Heavily weakened by a virus, Reed asks his teammates to stop the Hulk who is going on a rampage in New York City. Later, he finds a cure for his illness and the team regroups to fight back. Since the Hulk is battling his former teammates, the Fantastic Four decide to join forces with the Avengers, but having never fought side-by-side, they only get in each other's way. With more collaboration, they finally get rid of the Hulk who disappears into the Hudson River.
Just when Reed is about to propose to Sue, Johnny announces that she has been abducted by the Sub-Mariner. Determined to deal with his rival once and for all, Reed confronts the Sea Prince by himself. With the help of Doctor Strange, the rest of the team track them down. Sue tells Namor her heart belongs to Reed and Strange brings them back to safety.
The Fantastic Four are surprised by an attack from the X-Men. But when they learn that the Mad Thinker and the Puppet Master are behind this attack, the two teams join their efforts and the villains are forced to escape.
When he entered university, Reed Richards tried to befriend Victor von Doom, but the arrogant young man preferred to keep his privacy. Richards ended up sharing his dormitory with high school football star Benjamin Grimm, much to his pleasure.
Lady Dorma enlists the help of the Fantastic Four to defeat Attuma who threatens to overthrow Namor and might eventually attack the surface world. The team destroys the invader's arsenal, and while the Prince battles Attuma in a hand-to-hand combat, they covertly disable the villain's traps to even the odds.
Mr. Fantastic is taken with the Fantastic Four to Planet X where he saves Kurrgo's people who are doomed by the imminent collision of an asteroid with their world.
Reed confirms to Johnny that the sinking of houses in Glenville new housing development is not natural.
Doctor Doom tries to defeat the Fantastic Four by switching bodies with Mr. Fantastic and submitting them to a reducing machine but he gets caught under the ray and shrinks to nothingness.
Reed and Ben advise Sue not to interfere when she tries to dissuade her brother from tackling the Wizard alone.
The Fantastic Four have to deal with the Impossible Man whose ability to turn his body into anything he wants jeopardizes the safety of the planet. Reed's strategy to ignore him bears results when the alien gets bored and leaves.
Reed, Ben and Sue help the Human Torch after he has left the Fantastic Four to team up with the Acrobat who uses him in his criminal activities.
Mr. Fantastic reminds Johnny the trouble they causes when he joined the Acrobat the previous month.
Back on Earth, the Fantastic Four are acclaimed by the public for being the first people to return from the Moon. When the Invisible Girl is kidnapped, the team rescue her from the Sub-Mariner who was acting under the Puppet Master's control.
Reed, Sue and Ben offer their help to Johnny when he is publicly accused of being a spy, but the boy prefers to deal with the problem alone.
Reed, Sue and Ben advise Johnny to ignore the Asbestos Man's provocative letter.
The Fantastic Four learn that Doctor Doom has captured Spider-Man to force them to surrender. When they arrive to rescue the young hero, Doom has fled and they realize that the hero they rescued was an impostor.
Mr. Fantastic saves Johnny from a deadly fall after the young hero has heroically prevented a bomb from destroying a veteran's hospital.
Retelling of Spider-Man's first visit at the Fantastic Four headquarters.
The Teen Brigade asks the Fantastic Four for their help to locate the Hulk, but Mr. Fantastic replies that his team is too busy at the moment.
Warned by the Watcher, the Fantastic Four capture the Molecule Man, a man who can control molecules and poses a threat to the whole universe.
Mr. Fantastic tells the Human Torch to get Spider-Man's help to stop Sandman who has just escaped.
The Human Torch has to intervene when Doris is having a party at her house and Spider-Man decides to crash it. The rest of the Fantastic Four join the skirmish until Invisible Girl puts an end to it.
Iron Man seeks the help of the Fantastic Four to locate the Hulk, but they are too busy to comply.
During Reed's tests on her invisibility power, Sue accidentally discovers new abilities. The Fantastic Four are tricked into buying a small island to conduct larger scale experiments. They realize the whole thing is a set up when they are captured by the Mole Man. During their escape, the island and all its equipment are destroyed by Reed's sabotaging the Mole Man's control panels.
Mr. Fantastic advises the Human Torch not to jump to conclusions before he finds proof that the Eel has resumed his criminal activities.
Doctor Doom bails three criminals out of jail and gives them new unique abilities. The team is indeed captured, but Doom ends up falling through spatial breach.
Mr. Fantastic and the Thing rescue Johnny and Sue who have been trapped by the Wizard.
The Fantastic Four are helpless against an alien who uses New York as his new playground until Reed realizes that he is but a child so he finds his parents that come to Earth to recover their Infant Terrible.
The Fantastic Four have a short discussion about a newspaper article about the X-Men that compares Iceman to the Human Torch.
Johnny asks his teammates not to interfere while he deals with the Plantman.
The Fantastic Four hire Matt Murdock to review the legal aspects of their lease renewal while they leave for the capital to be awarded another medal, but when he fails to deliver his report the next day, they decide to hire someone faster.
The Fantastic Four are forced to surrender by the Red Ghost who leaves them stranded on the surface of the moon. But his ship crashes in the Blue Area of the Moon, and when he threatens Mr. Fantastic at gunpoint in the Watcher's Citadel, the Invisible Girl pushes him into a portal where he disappears. The Watcher sends them back home.
The Fantastic Four get a phone call from J. Jonah Jameson asking if they saw Spider-Man. Reed relays the message to Captain America at Avengers HQ.
Fantastic Four discover the castle of Diablo, an alchemist held in captivity by Transylvanian villagers who considered him too dangerous. After the Thing sets him free, the Fantastic Four discover that his science is a fraud and Diablo is forced to flee back in to his crypt.
Hearing that the Human Torch and the Thing have intercepted the Sub-Mariner on his way to New York Harbor, Reed arrives with Sue, explaining that the negotiation meeting he had arranged with the Sea Prince is ruined.
After the Thing has attacked the Human Torch while they were flying the Fantasti-Car, Reed discovers that he was under the Puppet Master's control and deduces that the Mad Thinker was also involved. He submits the Thing to a device that causes the radioactive puppet to backfire on the Puppet Master and knock him out.
Disgruntled again over the leadership of the Fantastic Four, Johnny and Ben decide to strike it off on their own and compete in race, but Reed teaches them a lesson by capturing them both.
During a reception at the Latverian Embassy, Doctor Doom drugs the Fantastic Four so they fight each other. But Reed Richards returns the favor and gives Doom the illusion that he vanquished his rival in a mental duel. With no more interest in the Fantastic Four, Doctor Doom leaves.
The Fantastic Four confront the Mole Man who has pulled entire city blocks underground, capturing the Invisible Girl in the process. When they go to her rescue and defeat the villain, Sue gets critically injured by an explosion. At the hospital, Johnny is shocked at the visit of his father whom he thought dead. Being the only physician able to save Sue, he is taken to the operating room and the surgery is successful.
When Sue and Johnny's father escapes from jail with super-powers, the Fantastic Four try to capture him without harming him. They eventually discover that he's the Super-Skrull and that Franklin Storm has been sent off the planet. Reed forces the aliens to trade the Super-Skrull with Dr. Storm. They send him back with a bomb and he dies as a hero, shielding the Fantastic Four from the blast.
Reed and Ben are cleverly set against one another by multibillionaire Gregory Gideon whose megalomania drove him to accept a challenge to destroy the Fantastic Four. But when his own son ends up back in time because of a trap he set for the heroes, Gideon runs to the Baxter Building and confesses to the Fantastic Four. After they bring back his son, Gideon comes to his senses and decides to renounce his fortune.
News that the Avengers plan to overthrow the American government reach the Fantastic Four who offer their help to defeat them, but the Pentagon wants no super-heroes on the streets.
Reed takes his teammates for a friendly visit to State University where he is supposed to give a lecture. After the speech, the inanimate dragon-like creature they saw earlier appears and attacks the Fantastic Four. Reed deduces that only Diablo could have made it alive. As Diablo attempts to destroy the team, Dragon-Man tries to protect Susan and both the creature and its new master end up at the bottom of a lake. When it's all over, Reed brings Suzan to a romantic spot on the campus where he officially renews his proposal to her.
Reed and Sue announce their engagement to the press. After the party, the couple and the Thing are attacked and rendered unconscious by the Frightful Four. With his Anti-Grav Disks, the Wizard sends them floating adrift along with Alicia, but they are rescued by the Human Torch. The Fantastic Four are about to defeat their evil counterpart when the Wizard's ship explodes, allowing the Frightful Four to escape.
At Sue's suggestion, the Fantastic Four travel to the Skrulls' home world to get some closure on her father's death. They get caught in an internal conflict between Franklin Storm's murderer and the Skrull King. After they saved the life of his daughter, the king informs them that they no longer need to fear an invasion from his race.
The Frightful Four capture Sue Storm then lure the rest of the Fantastic Four on a remote Pacific atoll where they leave them stranded until an atomic Q-Bomb explodes. A moment later, the Fantastic Four are unconscious floating at sea, unconscious yet protected by the Invisible Girl's force field.
After losing their powers due to the explosion of the Frightful Four's Q-Bomb, the Fantastic Four become vulnerable to their enemies so Reed tries to find ways to keep them from learning about it. When the heroes are suddenly attacked by Doctor Doom who has taken over their headquarters, Daredevil intervenes and protects them from the villain until Reed restores their powers with his Power-Stimulator, including the reluctant Ben. After defeating Doctor Doom by destroying his armor, the Thing announces to the team that he is quitting.
In the aftermath of their battle with Doctor Doom, the Fantastic Four must deal with the departure of the Thing. Attacked by the Frightful Four, they are shocked to see that their former teammate has switched sides, and with his help, the villains easily subdue the remaining members of the Fantastic Four. But soon, Reed and Sue manage to abduct Ben and try to cure him of his brainwashing. The Wizard decides to submit the Human Torch to the same treatment as the Thing. The Frightful Four attack the two and use the captured Human Torch as leverage to have the Fantastic Four surrender. But having the Thing back on their sides flips the tide for our heroes and although Madame Medusa is able to flee, her teammates are delivered to the police.
On Reed Richards and Sue Storm's wedding day at Baxter Building, the Red Ghost and his Super Apes attack the couple and Alicia Masters, but Doctor Strange banishes the villains to a distant nether world. Ben informs his team that too many of their old foes have joined forces to assault the building. As the major battle rages on, the Watcher shows up and takes Reed to his home planet where he lets him take a Sub-Atomic Time Displacer. He uses the machine to transport all their enemies back to the recent past with no memory of what occurred. Finally, Reed and Sue are wed in front of all their family and friends.
Hearing that Doctor Doom has captured the Avengers, the Fantastic Four get underway to lend a hand but Washington won't allow them to interfere in case this would precipitate a diplomatic conflict.