He posed as the Hippo to gain entry to solitary confinement in the Cage. His cell was next to Jackie's. He encouraged him to visit the Consultant, but he had no interest. He then posed as a patient harmed by Mr. Pain at the hospital where Dio had been admitted. The patient claimed that the Consultant had been responsible for enhancing Pain and advised Dio to do the same, but he refused. The Consultant then tipped Dio off on one of the Owls' operations, knowing it would lead Dio to be in contact with the SS2 gas.
He posed as a doctor when Jackie was infected by the SS2 gas, a variant of the Super-Soldier Serum. He tested Jackie's reflexes by firing on him. He got a shot that cleared up Jackie's dizziness, but hampered his vision, so he gave Jackie a special set of sunglasses that would help. He then subtly offered information about the Owls' operations to Jackie. He slipped a card advertising the Mechanic to Jackie, who was soon hurt in a fight with Grizzly and Boomerang. Jackie went to the Mechanic for new weapons.
As the Mechanic, he showed Jackie how to use his special glasses and equipped him with special guns with Adamantium bullets. He posed as a doctor in a prison hospital after Jackie Dio was shot by several cops. Wanting a monetary return on his investment he injected him with a Healing factor to save him from death. He left behind a note stated he needed payment. After Jackie finally killed Mr. Pain, the Consultant revealed himself, told Jackie to take the codename Underworld, and demanded payment soon.