Victor Zsasz is the most unrepentant of sociopaths, a serial killer who marks the death of his victims on his skin with tall marks. He believes that human beings are mindless 'robots' who attempt to give themselves purpose and meaning by materialistic and shallow means. He is very intelligent and deceptively cunning, often trying to manipulate or intimidate his victims before killing them and arranging them in lifelike poses for the police and Batman to find.

Mr. Zsasz lived a privileged existence. He had a loving, wealthy family and graduated top of his class in college, later going on to amass his own fortune of his own through various companies. At the age of 25, his parents tragically died in a boating accident, and while he accepted what had happened, Zsasz could not help but feel depressed at their loss. In an attempt to distract himself from his growing depression, Zsasz became swept up in high stakes gambling. He neglected his companies while gaining, and just as often losing, huge sums of money in card games. It all came to a head in one game, in which Zsasz bet everything to his name in a game against the Penguin and lost. It was then that Zsasz realized that no amount of wealth could change the hollow person he had become or give any meaning to his life, and he fled the casino to attempt suicide at the Gotham Bridge. Before he could jump, a transient threatened him with a knife for whatever he had on him. Zsasz fought back and, upon looking into the homeless man's eyes, realized he was just as empty as he himself was. He killed the man and decided to free 'zombies' of their mortal coils, cutting a notch in himself for each one to remind himself that he too was a human like them; a choice that has caused him to have numerous run-ins with Batman and landed him in Arkham Asylum and Blackgate almost as many times.

In The Last Arkham, his first original appearance, he has already 47 known victims. Jeremiah Arkham describes him as serial killer without apparent motif, too clever and dangerous that seems unconcerned. A challenge for psychiatry. Zsasz uses hidden tunnels to escape from Arkham and kills a family, two students and one pedestrian, each murder was carried out with a knife, his favorite weapon, and putting them as if they were still alive. Batman pretend to kill an officer and get caught in Arkham so he can be near Zsasz and expose him. While Batman was in the asylum, Zsasz convinces Jeremiah to reunite all the inmates and confront them against Batman. After that, Victor kills Zolly Hiram, architect in charge of reconstruction of asylum and designer of the tunnels offered to the highest bidder, making it appear like he had committed suicide and Everard Mallitt, the only inmate who knew about the existence of the tunnels. With the help of Nightwing, Batman solved the mystery of his crimes. At the end Zsasz almost kills Nightwing but is beaten by Batman and returned to his cell.

During Knightfall, he held a school of girls hostage. Batman came on seen and promptly clashed with the villain. During the fight, Zsasz injured Batman and taunted him with the notion that they were more alike than Batman could like to think, relating their method of hunting down others and insinuating that Batman got just as much enjoyment over attacking the guilty as Zsasz did the innocent. This threw Batman into an almost uncontrolled rage, causing him to viciously beat Zsasz almost to the point of lethality before he was stopped by the police and Zsasz was properly apprehended.

When he escaped prison a little while afterward, he attacked Alfred Pennyworth while Bruce Wayne was at a charity event. However, because Alfred was rushed to a hospital before he could die and after a mark had already been carved for him, Zsasz became hellbent on finishing the job and killing the butler. Batman fought once with the killer before losing him when the police, who were going after both men, intervened in their fight and inadvertently allowed Zsasz to escape. In a risky move, he lured Zsasz to Alfred's location and managed to subdue and apprehend him seconds before he could kill Alfred.

In the No Man's Land storyline, Mr. Zsasz is the leader of a gang of thugs. He is severely injured and ends up being treated by Leslie Thomkins. Even while he is unconscious he is heavily restrained, although it is not enough to stop him from attacking Leslie's assistant with only his fingernails in his sleep. He is later almost killed by Killer Croc, as he was responsible for the death of his best friend and right-hand man. Upon finally waking, he threatens and almost kills Leslie, but is swiftly stopped and captured by Batman, Batgirl ( Cassandra Cain), and Huntress.

In the Joker's Last Laugh storyline Mr. Zsasz is turned into a Joker-like Zsasz and participates in a riot a Arkham Asylum where he attempts to kill Robin ( Tim Drake).

Mr. Zsasz joins Alexander Luthor's Secret Society of Super Villains. In Gotham Underground, he was paid to kill Matches Malone aka Bruce Wayne but failed. He did manage to inflict bloodshed on him.

In Batman War Drums, after murdering a man on a subway, Mr. Zsasz flees into the subway tunnels he had been living in. Batman and Robin ( Stephanie Brown) pursue him in the tunnels where he claims another victim. Robin goes to follow him and is kidnapped, luckily with Batman not far behind. Batman and Zsasz fight, both landing hits on each other, before Zsasz manages to gain to upper hand. An injured Robin comes to Batman's rescue and attacks Zsasz with a potentially fatal move which she is later reprimanded by Batman for.

Later, in Battle for the Cowl, Zsasz is one of the Arkham inmates forced to work for Black Mask. He becomes one of Black Mask's more trusted agents, and is given free reign to do as he wishes. Eventually, in Streets of Gotham, Zsasz rescues Black Mask from a fiery demise as thanks for previously freeing him from Arkham. Black Mask later gives him a great deal of money to fulfill whatever his desires might be, and with it Mr. Zsasz starts up a gladiatorial arena in which children are forced to first fight each-other before facing off with Zsasz himself. Batman ( d**k Grayson) and Robin ( Damian Wayne) go to investigate. Robin lets himself be captured without Batman's knowledge but finds that Zsasz is an incredibly difficult opponent, and is incapacitated quickly. Before Zsasz can deliver the killing blow, he is stopped by Abuse, who had been captured alongside Robin. After Robin recovers enough to fight again, he attacks Zsasz and finally overwhelms him to the point where Zsasz no longer sees him as a helpless victim. As per Abuse's wishes, though, Robin deals a less than lethal blow. Zsasz's current whereabouts are unknown.

Zsasz is highly intelligent and highly skilled in both combat and tactics, making him trouble for the both police and Batman.

He is highly unpredictable, killing people at random and killings have no real connection, and possesses no superhuman abilities unlike many of the Dark Knight's other enemies. He is a very capable killer, as proven in Detective Comics 815 where he kills four policemen and an Arkham psychologist without using any weapons except for a pen and four metal poles attached to a collar he is restrained with. In the same comic, he accurately throws a knife into the torso of a police officer from a distance. He is incredibly agile and has even been able to sneak up on Batman undetected on several occasions.

Height: 5'8"
Weight: 150
Eyes: Blue
Hair: Blonde, usually shaved
Shoe Size: 12
Weapon of Choice: Knives and hand-to-hand combat skills
Unusual Characteristics: Zsasz is covered almost head to toe in the tally mark scars he uses to count his victims.