Simonson, who had been writing the team comic The Avengers, had gotten approval for Reed and Sue to join that team after Engelhart had written them out of Fantastic Four. Yet by The Avengers #300, where they were scheduled to join the team, Simonson was told the characters were returning to Fantastic Four. This led to Simonson quitting The Avengers after that issue. Shortly afterward, he was offered the job of writing Fantastic Four. Having already prepared a number of stories involving the Avengers with Reed and Sue in the lineup, he then rewrote these for Fantastic Four. Simonson later recalled that working on Fantastic Four allowed him the latitude to use original Avengers members Thor and Iron Man, which he had been precluded from using in The Avengers.
