Jack Prosper was on a stakeout with his squad to take down the Commission (the Ultraverse version of the NY mob). During the outting, the Commission's Ultra Bonecrusher killed his entire squad and left Jack broken and near death. With his injuries driving him insane, he checked himself out of the hospital as quick as he could and, went to have his body enhanced by every back alley surgeon he could find to gain the powers of an Ultra himself.
With his new powers he set out to find Bonecrusher and get revenge for destroying his body. He began by trying to put the entire Commission into a state of disarray by blowing all as many of their installations as he could. This brought him into custody by Ultraforce. Once they heard his story, the decided that he had the best of chance of any of them to track Bonecrusher down so they struck a deal with him to let him work with them to bring the Ultra down.
When they found him, Wreckage (as his final surgeon had dubbed him) took down Bonecrusher and, when it was time to kill him, decided to turn him over to the authorities as Ultraforce wanted him to. Following this, he joined the Ultraforce as a full fledged member of the team.