Derek Murdock

Broad and heavyset, Derek carries long dark brown hair along with a full beard and green eyes. For a uniform he wears the standard gear issued to members of the Callisto Liberation Front.

Much like his brothers, Derek tends toward clumsy incompetence. He follows every command his mother issues as faithfully as he can manage, even though his string of failures leaves her with almost no patience for him.

As part of a scheme to halt Kao Construction's terraforming of Callisto, Derek joins his brothers Ron and Harrison in seizing an opera house where the firm's chief executive, Loren Cadena, is in attendance. With Cadena captured, Derek grabs a second hostage named Mark Manly, then rolls out a holo-device that projects his mother, Maria, who names the group the Callisto Liberation Front and rebukes Cadena for the harm the company has done. The plan is to detonate a spore grenade on Mark as a warning, but Mark knocks the device from Derek's hand, activating it, and its spores turn Cadena into a tree. With their hostage gone and other patrons transformed, the brothers flee in a ship they steal from Faye Valentine.

Back at their base, Maria scolds them over Cadena's death and pins most of the blame on Harrison. When Mark's phone rings, it comes out that he too had been taken as a hostage. Maria then reveals that the missiles central to her plan are held by the siblings' father, Howard Culpepper, and the group sets off for Ganymede to retrieve them, with Harrison finishing off Mark and stripping Faye's ship of anything valuable before they go.

Acting on a tip Faye supplies, Jet, Spike, and Faye track the family to the Kao Construction site. Maria orders Ron and Derek to arm and ready the missiles while she and Harrison prepare their ship. Faye ambushes the pair heading for the vessel, but Harrison shakes her off and escapes with Maria, leaving the two brothers behind. Derek and Ron keep working until Jet and Spike knock them out and shut the launch down.