Johnny Kelly was born in New York City in 1910, a kid in the neighborhood during prohibition who had dreams of being something big. He wanted to be as great as Al Capone and some of the other gangsters. As a pre-Immortal, he worked for a bootlegger, Gino DiGennaro, running numbers and booze. MacLeod met Johnny while playing poker with Gino. Johnny went outside to get more whiskey for Gino after the poker game and saw a hit go down. The cops interrogated Johnny and he told the cops nothing. Johnny then told Duncan to tell Gino that he quit.
Later that night, he went to a rival bootlegger and offered to join his organization, but winds up getting shot. The rival gang then dumped Johnny's body in front of Gino's plac,e and Duncan went outside to wait for Johnny's revival into immortality. Duncan then told Johnny what he was and what the rules were. He was ready to take Johnny as his pupil, but the new immortal didn't care about the rules, he wanted revenge. Johnny makes his first hit on theman who had killed him, making $3,000.
Over the years, Johnny learned how to use a sword by watching pirate movies. Eventually he decided to continue working as an assassin, and as the years passed began getting $200,000 a hit, and became a master of disguise.
In 1996, Johnny went to the corporate headquarters of a businessman, wearing artificial legs to make him look taller. Johnny killed his mark and escaped, took off his disguise, put on street clothes, and left the building riding a skateboard.
Johnny was at his storage unit in a warehouse when he saw Duncan MacLeod again. Since MacLeod could ID him, Johnny shot Duncan in the back and was about to take his head until two men arrived in the elevator and Johnny ran off. Later, Johnny tried to kill Duncan with a bomb planted in the trailer where he had been staying, but Duncan escaped.
Johnny later phoned Duncan and Duncan said that he would pay Johnny to target someone else, offering him $100,000. Johnny said he'd consider it, and they set a meet in a church. There, Duncan taunted Johnny who told Duncan that his hit list numbered 249 people and no one knew his face. MacLeod and Joe Dawson had set Johnny up in order to get his photo, and as Johnny stepped outside the Church, Joe posing as a photographer for the wedding which had just ended, took pictures of Johnny.
The next day, Johnny disguised as a hot dog vendor, about to do a hit, sees pictures of him plastered up all over town, which has ended his anonymity so necessary for an assassin. Johnny called Duncan and told him he was a dead man. Johnny tried to shoot Duncan with a rifle and hit a dummy which MacLeod had set up as a target, Johnny then sensed the presence of another Immortal, as MacLeod approached him. He and MacLeod face off, but a man who learned fencing by watching pirate movies was no match for MacLeod who defeated him and received his Quickening.
Kelly used an Italian style broadsword. According to Rudy Bryant, Watchers Associate Curator for Bladed Weapons When you learn how to sword fight from pirate movies, it makes sense that a pirate sword is what you'll fight with. This Italian-style broadsword is of an interesting design. It has a guard similar to a rapier...of course...Johnny K was prone to shooting first and taking heads later." During his fight with MacLeod, he used at least two auxiliary weapons; a stun gun and a Bowie knife. While the use of similar auxiliary weapons are used in many forms of martial arts across the world, Johnny's use was less a form of technique so much as an underhanded surprise attack. He showed a disregard for any form of the honor in battle even some of the evil immortals show. As he was effectively raised by gangsters, this is no surprise.