- You may also be looking for the episode "Lock-Up"
Lyle Bolton was Arkham Asylum's former head of security, who eventually became the villain Lock-Up.
Lyle Bolton acted as head of security for Wayne Enterprises before being hired as Arkham's chief of security, apparently on Bruce Wayne's recommendation. Knowing Arkham's history of escaped prisoners, Bolton vowed that none would escape as long as he was in charge. Unfortunately, he expressed his hatred of the inmates with cruel punishments, such as denying them privileges even when they behaved, chaining them in their cells every night, and electrifying their cell doors to prevent escape. He even held Arnold Wesker's puppet Scarface over a can filled with termites to terrorize him. His regime managed to cow the inmates into doing whatever he wanted, hoping to escape even more terrible punishment.
Even the Scarecrow, the self-proclaimed master of fear, escaped Arkham out of sheer terror of Bolton. When Batman apprehended the Scarecrow and returned him to Arkham, Bolton was present to take the gibbering villain into custody-he thanked the heroic duo and swore that the Scarecrow was the first-and last-prisoner to escape Arkham under his watch. His words and gratitude were sincere, but his menacing demeanor towards Scarecrow and the latter's terrified reactions caused Batman and Robin to become suspicious.
The next day, Bruce Wayne requested an inquiry into Bolton's behavior, leading to a court hearing. During the hearing, Bolton protested the accusations with civil earnestness. Several inmates were questioned, but Bolton intimidated them into silence with a glare. However, Wayne was able to provoke a reaction by suggesting that Bolton's tenure as Arkham's chief of security be extended for another eighteen months. At that, Harley Quinn, the Ventriloquist, and the Scarecrow desperately burst out and accused Bolton of verbally assaulting and physically abusing them. Scarface, being the puppet that he is (even if the Ventriloquist had multiple personality disorder), expressed his terror over the termite episode. Enraged by the prisoners' defiance, Bolton attempted to kill the inmates, and was restrained and fired from his post. Now blaming the police, the bureaucrats and the doctors for coddling the villains, Bolton's mind snapped, and he decided to punish all of them.
Six months later, Bolton resurfaced as Lock-Up, proclaiming himself an ally of Batman: the latter would catch the crooks, and he would imprison them. When Batman made clear that he would not tolerate Lock-Up's behavior, Lock-Up declared him his enemy. A short fight broke out, but Lock-Up managed to escape.
Abducting Summer Gleeson, Mayor Hamilton Hill, Dr. Bartholomew and Commissioner James Gordon, Lock-Up held them aboard a decommissioned ship off the coast of Stonegate Penitentiary, where he had previously worked. Batman and Robin tracked Lock-Up down, and Batman engaged him while Robin freed his prisoners. During their fight, Lock-Up expressed frank astonishment that Batman would actually care about the fates of Arkham's inmates, or be opposed to Lock-Up's brand of order.
After his capture, Bolton was deemed insane and - ironically enough - locked in Arkham. Despite being surrounded by his vengeful former inmates, he concluded that he was in the best possible position—now, nobody would ever escape his watch.
Lyle Bolton was dedicated to keeping Gotham safe from crime; unfortunately, this manifested as a near-pathological hatred of criminals. He showed no mercy to any of his inmates, using many cruel and unusual disciplinary measures even when they displayed exemplary behavior. He even seemed willing to murder the inmates if they went against his wishes-because of this, the residents of Arkham were absolutely terrified of him.
Initially, Bolton's animosity was reserved for the criminal element; he was cordial, if somewhat gruff, to his peers, subordinates, and superiors alike. After being prevented from killing the inmates of Arkham when they revealed his sadistic treatment of them, he shifted his hatred to the courts, police, and doctors, accusing them of "coddling" the criminals. In his guise of "Lock-Up", he began targeting everyone he considered to be a contributor to Gotham's crime problem, imprisoning them in a ship near his first job site - Stonegate Penitentiary.
Bolton admired Batman, seeing him as the other side of the war against crime. He seemed honestly surprised that Batman disagreed with his methods, and concluded that even the Caped Crusader was too soft on crime. Despite this, he was pleased to be brought to Arkham, as he felt it would allow him to keep watch over all of the inmates - but how much of this is an inability to admit his mistakes is unknown.
Because of all this, Bolton is an arrogant control freak who sees the world in black and white: those who are with him and those who are against him and of course sees anyone who so much as says "no" to him as a bad guy to the point where he instantly labels them an enemy.
Lock-Up was one of several characters created for the DCAU who were eventually adapted into the mainstream comics. Interestingly, his adaptation predated that of Harley Quinn, the most popular and prominent example of such characters.
His role in the comics is similarly that of a vigilante jailer. During the No Man's Land storyline, when public order has broken down completely in Gotham after a catastrophic earthquake, Lock-Up and Batman do in fact ally, with Lock-Up serving as warden of Blackgate Prison, to keep the inmates inside from overrunning the city.