Cabell is the only Robotech Master Scientist left on the moon Fantoma, the Master's homeworld. He has chosen to stay behind to continue with his protoculture experiments with his assistant and friend Rem. Cabell believes he may be on the verge of unlocking Zor's lost secrets about protoculture. Without a doubt, Cabell is a genius and "the" authority regarding protoculture.
Cabell is a dedicated scientist whose curiosity is tempered with patience and compassion for all life. In this respect he is an aberration the society ruled by the heartless Robotech Masters. It was this perceived weakness in his character that convinced the Masters to leave him to his work on Fantoma (rather than accompany them to Earth).
NOTE: The script outline develops the father-son friendship between Cabell and Rem. Both join the REF to help destroy the Invid. Doctor Lang and Cabell quickly become friends and allies. It appears that Cabell dies in the arms of Rem about halfway through the series (revealing that Rem is a Zor clone).