Born in Castre Gregory, Ter Mair, Pedr Brecryg was the son of Garth Brecryg, a fairly wealthy businessman. As such, Pedr had a good upbringing, and an excellent education.
Pedr was always very bright, but his exposure to the Alteration (to which he had a delayed reaction) increased his intelligence considerably.
Allong with his augmented super-intelligence, Brainbox has various technological devices to assist him, notably his neuro-kinetic polycables. Recently, since the graphic novel Thunder Rabbit, Brainbox has exhibited powerful psychic abilities. He is currently being tought how to control them by Nightingale and Morning Sun.
Brainbox is supported by Storm and Surge, and later by Blitz and Thunderman, although he currently acts as chief technical supervisor to Teen-Righteous
Typically, Brainbox fights the same enemies as Storm and Surge, but the kawar Overload has developed a particular hatred towards him for defeating it in Thunder Rabbit.
Brainbox joined the League of Righteousness, sometime after the League's formation.
Brainbox was one of the founding members of the League of Righteousness's Junior Squad, usually known as Teen-Righteous.