Mister Fantastic is a superhero appearing in American comic books published by Marvel Comics. He was created by Stan Lee and Jack Kirby. The character is a founding member and the leader of the Fantastic Four. Richards has a mastery of mechanical, aerospace and electrical engineering, chemistry, all levels of physics, and human and alien biology. BusinessWeek listed Mister Fantastic as one of the top ten most intelligent fictional characters in American comics. He is the inventor of the spacecraft that was bombarded by cosmic radiation on its maiden voyage, granting the Fantastic Four their powers. Richards gained the ability to stretch his body into any shape he desires.

Valeria Meghan Richards, originally von Doom, is a fictional character appearing in American comic books published by Marvel Comics. The character has been depicted as the daughter of Mister Fantastic and the Invisible Woman and goddaughter of Doctor Victor von Doom. She is the younger sister of Franklin Richards. Valeria made her first appearance under the code name Marvel Girl and is currently using the name Brainstorm.