Little is known of Dr. Mandibus except for the fact that an undetermined amount of time ago, he set himself up as the only criminal surgeon in his sector. At one point he was contacted by Geatar, the first mate of Nebula. Geatar made arrangements with Dr. Mandibus for Mandibus to repair Nebula's extensive injuries. After many hours of surgery, Mandibus came out and to his waiting room and told Geatar he was finished. Geatar got all anxious and picked Mandibus up and demanded to know Nebula's condition. Mandibus held his finger scalpel up to Geatar's throat and was promptly put down. He then announced that his procedure was a complete success. He then brought in Nebula, who was as good as new, with some cybernetic enhancements, specifically her left arm and left side of her face.