"Go find yourself another monkey!"
Negative Man aka Larry Trainor was an expert pilot for the United States Air Force. Afterwards, he became a test pilot and friend of Hal Jordan. Trainor took on an unusual mission to pilot an experimental test rocket, the X-19. A malfunction sent him into deep space where he passed by a radiation belt and was exposed to cosmic energy. After returning to Earth, Trainor found he could manifest this energy as a superpowered being called the Negative and controlled it with his mind.
Professor Caulder approached him and offered special material that would help contain the radiation. Taking the name Negative Man, he joined the Doom Patrol. The Negative could only be out of his body for 60 seconds or else Negative Man would die. While in this form, he can fly, phase through solid objects, and either absorb or project energy in various forms. After the Paris battle against General Zahl, Negative Man quit and wandered. Eventually, he worked for a circus that also included Flex Mentallo, Shasta the Living Mountain, The Bountiful Baboushka, Dorothy Spinner, Romulus & Remus as the Siamese Aerialists, Beast Boy, and Lodestone the Woman Who Can See the Future. After a few months, Negative Man quit but was attacked by Animal-Vegetable-Mineral Man. The Chief, Elastigirl, and Batman convinced him to help. They then found Robotman and the Arsenal. After being put to the test by General Zahl, the Doom Patrol sacrificed their lives.