Dr. J. S. Steinman, M.D., is the main antagonist of the second level of BioShock, the Medical Pavilion. He is referred to as the 'Picasso of Surgery' in the game.
An accomplished surgeon, Steinman was recruited by Ryan and soon rose to a degree of notoriety throughout Rapture after setting up a medical practice on the Medical Pavilion in Rapture.
Steinman used the discovery of ADAM to augment his cosmetic surgical procedures. However, he soon began to feel the effects of ADAM addiction himself and was slowly driven mad whilst at the same time mutilating his patients.
He murders his nurse when she threatens to report him to the Rapture constabulary and, after finally running out of willing patients, continues his cosmetic experiments on Splicers.