While one of the biggest -- and certainly most surprising -- stories to come out of the first day of Comic-Con International is that Legion creator Nah Hawley is developing a Doctor Doom film, that's apparently not the extent of Fox's plans for its struggling Fantastic Four franchise.

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Buried deep within the Hollywood Reporter article is the rumor that The LEGO Batman Movie co-writer Seth Grahame-Smith is already at work on a Fantastic Four spinoff centering on Franklin Richards, the son of Mister Fantastic and the Invisible Woman. It seemingly confirms a report published last month by Bleeding Cool that Fox is plotting a kids movie featuring Franklin and his younger sister Valeria, with The Thing and the Human Torch.

Introduced in 1968's Fantastic Four Annual #6, Franklin is a mutant with a vast array of psionic abilities, ranging from reality warping and matter manipulation to telekinesis and precognition, the extent of which seems limited only by his youth. Long a supporting character in Marvel's Fantastic Four comics, Franklin has also been associated over the years with Power Pack, where he went by the code name Tattletale, and Generation X, which helped to look after him during his parents' absence. He also starred in Franklin Richards: Son of a Genius, a series of humorous one-shots by Chris Eliopoulos and Marc Sumerak.

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Franklin has also played a significant role within the larger Marvel Universe, such as when he created the "Heroes Reborn" pocket universe to contain the heroes (including his parents) who seemingly died in a battle against Onslaught.

The rumored spinoff, like Hawley's Doctor Doom movie, is characterized as part of Fox's effort to revive and reimagine the Fantastic Four franchise following the performance of Josh Trank's 2015 reboot.