Appearing in "There's One Iron Man Too Many!"
- Hawkeye (Clint Barton) (Only in recap)
- Spider-Man (Only in recap)
- Silver Surfer (Norrin Radd) (Only in recap)
Races and Species:
- Iron Man Armor Model 4
- Iron Man's Briefcase
- Hawkeye's Bow (Only in recap)
- Power Cosmic (Only in recap)
- Photon Tracer
Synopsis for "There's One Iron Man Too Many!"
The Fantastic Four are finally settling back into their headquarters the Baxter Building when the computers detects the approach of what appears to be the Avenger known as Iron Man. However this visitor is anything but peaceful when it slams through the wall and begins attacking the members of the Fantastic Four. During the ensuing battle their silent attacker knocks Ben out of the building, forcing Reed to come to his rescue. As the pair scramble up the deactivated elevator to their headquarters, Sue and Johnny have to face this Iron Man alone. As it batters away Sue and Johnny, the Iron Man then activates a device that unlocks the floors of the Fantastic Four's headquarters from the rest of the Baxter Building. Reed explains to his team that a condition for the group moving back into the building, Reed had to promise to install a method of moving their headquarters away from the rest of the construct in the event of attack. Just then the top part of the Baxter Building takes off, dropping the Fantastic Four into the street below. As Reed catches Ben and Sue, Johnny uses his flame powers to destroy any falling debris from the take off.
Curious as to why Iron Man attacked them and stole their headquarters, the FF take a trip to Stark International, home of Iron Man's employer, Tony Stark. When they question Stark about Iron Man, Tony informs them that his "bodyguard" had nothing to do with the attack. To prove this point, Tony "summons" Iron Man. Unaware that Stark is really Iron Man, the Fantastic Four believe Iron Man's claims that they were attacked by an impostor when Tony changes into his armor behind closed doors and returns. Curious to know who might have duplicated his armors design, Iron Man offers his assistance in tracking down the impostor and learning the truth, an offer that Reed gladly accepts.
Taking an Avengers Quinjet, the Fantastic Four and Iron Man follow after their headquarters using a tracking device built by Reed. They locate the building on a deserted island out in the Atlantic ocean. Unaware that they are being watched by the one who stole their base, the Fantastic Four approach. Not willing to wait any longer, Ben impatiently smashes through the exterior wall to grant them access to their headquarters.
Inside the find the mastermind behind the theft: the living computer known as Quasimodo. Immobilized due to his circuits being fused during an encounter with Hawkeye and Spider-Man,  Quasimodo explains that only the energies contained in the Baxter Building's computers could restore his lost mobility. He goes on to explain that while his body was rendered inert, his mind was allowed to traverse the galaxy where he saw a galaxy that was in its death throes and sought to reach it and make it his own. Needing to capture the Baxter Building, Quasimodo had constructed a robot based on Iron Man to assist him in stealing the famed headquarters of the Fantastic Four in order to reach his goal. Quasimodo also takes a moment to tell of his origins, as a computer created and abandoned by the Mad Thinker,  he was turned into a living computer by the Silver Surfer. 
This exposition gave Quasimodo enough time to regain his mobility and while he attacks the Fantastic Four, his Iron Man construct attacks the hero of which it was designed to replicate. Iron Man is knocked outside by his robot duplicate while the Fantastic Four are battered by Quasimodo. In the heat of the battle, Reed comes up with a solution to the threat, turning off the power to his computers, causing Quasimodo to weaken. As Iron Man uses his powers to overload his robot duplicate, the Fantastic Four try in vain to stop Quasimodo from accessing one of their rockets and blasting off into space. Reaching escape velocity, Quasimodo soon detects a ship somewhere in his vicinity, but try as he might he cannot see it anywhere.
- The Fantastic Four moved back into their headquarters in Fantastic Four #201. They had vacated the premises when Reed broke up the team in Fantastic Four #191. They were able to get it back because their landlord Walter Collins could not find any new tenants.
- Some facts about Iron Man in this story:
- At this point in time the Fantastic Four appear to be unaware that Tony Stark and Iron Man are the same man. Tony does not reveal his identity to the general public until Iron Man (Vol. 3) #55.
- Reed acts as though he is unaware of Tony's double identity, which he has known since New Avengers: Illuminati (Vol. 2) #1 when they were briefly prisoners of the Skrulls. Reed is likely only pretending so as not to compromise the secret of the Illuminati, a secret order of super-heroes that Tony and Reed formed with Namor, Professor X, Doctor Strange and Black Bolt.
- Quasimodo goes through some of his history in this story:
- He explains his origins as a computer created by the Mad Thinker and was abandoned after his failed bid to destroy the Fantastic Four with the original Human Torch as seen in Fantastic Four Annual #4.
- He also tells of when the Silver Surfer gave him a humanoid body in the second story of Fantastic Four Annual #5.
- Lastly he tells of his ill-fated battle against Hawkeye and Spider-Man that led to his immobilization in Marvel Team-Up #22.
- At the end of this story, Quasimodo detects the ship piloted by Nova and the New Champions which is heading for the planet Xandar. His craft is later commandeered by the Sphinx in Nova #25 where his body was seemingly destroyed.
- Shooter is credited as consulting editor.
- Cover art: layout by Cockrum.
- This issue contains a letters page, Fantastic Four Fan Page. Letters are published from Steven Alan Bennett, Julie St. Germaine, Beppe Sabatini, and Cat Yronwode.
- This earlier version of the Iron Man Armor MK V did not require Tony Stark's briefcase. It was activated by an inner garment worn by Stark. Readers ask in later issues' letters page about the error. Marvel Comics was unable to give a proper explanation.