Stalker was once a normal hunter in Africa until he was mauled by a black panther. He then had to have his spine repaired, which gave him enhanced senses, super strength, and agility. He found that these enhancements made hunting animals too easy and sought out more dangerous foes. With that in mind, he set his sights on Terry McGinnis (Batman). He lured Batman into a trap by using Terry's brother Matt as bait. They fought fiercely, but Batman came up the victor and Stalker was assumed dead after being struck by a bullet train.
As it turns out, Stalker did survive his encounter with the bullet train. It seems that Stalker may have had connections to Kobra's leading geneticist Dr. Abel Cuvier because Stalker has taken residency on a secluded volcanic island in the North Sea where he could hunt genetically altered game. Each specimen is a game animal like a lion, a bear or even a gorilla but they each have dinosaur DNA that was spliced with their genetic structure. Unfortunately, Howard Groote, Terry's geeky, overweight friend, had booked a camping trip to Stalker's island without knowing the impending danger.
After their arrival, Dana Tan, Maxine Gibson and Howard are attacked by a genetically altered gorilla. Terry manages to distract the animal while the others get away but they end up getting caught in one of Stalker's traps. Terry tries to spring them from the trap but the steel bars are electrified. Terry tells his friends that he will go for help but Maxine knows better because by this time, she is already working with Terry as his techno savy ally. As Batman, Terry captures the gorilla with his bat-bola and then Stalker appears.
Stalker informs Batman that he has genetically designed his game to have a short lifespan but at the same time, they serve the purpose of strengthening Stalker's hunting prowess. Stalker invites Batman to join him in the hunt of these animals but Terry refuses so Stalker releases all the animals that he has had in captivity into the wild. Terry has no choice but wrangle every one of these animals before they get to his friends. Terry and Stalker are successful in the hunt but of course, Stalker killed all of his catches. The only animal that they didn't catch, was spliced with T-Rex DNA and Stalker had counted on Terry rounding up all the other animals in one section of the island in order to use them as bait.
The giant animal was drawn to the noises of the other animals and Stalker told Batman to stay out of this because Stalker has made this animal his ultimate trophy. Terry ignores Stalker and uses a tranq gun to knock out the creature. Angered by this, Stalker attacks Terry but only to have himself fall into one of his own traps that Terry set up during the hunt. Terry takes Stalker's remote control which is wired to the island and uses it to release his friends while at the same time, activating an emergency beacon to contact harbor patrol.
After being brought into custody, Stalker is released into Agent Bennett's custody because Bennett needs someone who is familiar with Kobra's operations and Stalker has superior tracking skills which enable him to locate Kobra's secret agent False Face. He later returns to Gotham, but instead of hunting Batman, he helps Terry stop the criminal gang known as Kobra from changing the worlds ecosystem so that it could only support reptilian life. He ends up saving Batman's life, saying that if he was going to die, it would be at his hands.
Stalker was impressed by the way Batman handled himself against Kobra so he decides to make Batman either his protege or his ultimate prey once again. Stalker tracks down Terry while he is with Dana and Maxine. Stalker aims a dart at Terry's neck and fires. Terry looks around and finds Stalker prowling around a nearby rooftop. Maxine invites Dana to dinner while Terry pretends to act sick so he can make a quick getaway. Stalker surprises Terry as he was calling Bruce for help. As Stalker attacks Terry, Terry begins to anticipate every one of Stalker's moves. Stalker submits to Terry's determination and begins to taunt Terry on whether or not he is prey or a hunter.
In one brief moment, Terry recalls all the anguish that Stalker had brought him and the cold hard fact that only one of them can survive this hunt. Terry grabs Stalker's spear and even though he has chance to impale Stalker, he doesn't take it. Stalker escapes and Terry heads back to the Batcave. After examining Terry's vitals, Bruce discovers that Stalker had injected Terry with geno-steroids which gave him his enhanced senses and skills. Bruce also realized that the steroid was laced with a radioactive signature. Bruce tells Terry to sleep off this bad night and to watch his back since Stalker knows where Terry lives.
Terry takes advantage of Stalker's knowledge by placing a dummy in his bed as decoy. The decoy works and Stalker was thoroughly impressed by Terry's ingenuity. Stalker explains why he gave Terry his enhanced abilities and why Terry's body is emitting a low level radioactive signature. The island that Stalker lived on, also became the home of Derek Powers aka Blight. The strong currents in Gotham Bay washed up Blight onto Stalker's island after the sub that Blight was on sank. Blight had amnesia but the only things he could recall is his identity and his hatred for Batman.
Stalker observed Blight's movements until Blight made his way back to Gotham City after he had touched radioactive material from a sunken vessel that laid beneath the shores of Stalker's island. Stalker figured that the radioactive material must have awakened certain memories inside Blight after he had touched it. Stalker now knew why Blight was heading back to Gotham and he couldn't allow Blight to kill Batman because the honor of killing Batman was Stalker's. Terry soon realizes that Stalker has made him bait since the raidoactive signature in Terry's body will draw out Blight. Blight arrives at a steel mill where Terry and Stalker were waiting for him.
As Terry and Blight combat each other, Blight begins to remember more about his past life. Blight defeats Terry and just as he is about to deliver the final blow, Stalker releases a vat of molten lead on Blight. Terry regains consciousness for a moment to see that Blight is encased in lead. Stalker applauds Terry for his cooperation in this hunt and rewards him with a shock from his spear. Terry is knocked out for half an hour until Bruce's bellowing voice wakes him up. Bruce comforts Terry in the fact that Blight will remain inert in the lead and Stalker has allowed Terry to survive for the time being. Meanwhile, Stalker has taken his trophy back to a cave on his island. Blight has now become Stalker's latest prize in the thrill of the hunt.
It is implied that Stalker was killed by Hush (the clone of Dick Grayson created by Project Cadmus) when Hush escaped from the facility where he was being held and began killing old as well as new Batman villains. However, there is a temporal paradox involved in Stalker's murder. During the "Epilogue" episode of Justice League Unlimited, Stalker is shown with Shriek, Inque and Parasite, who are attacking the Justice League Beyond. This event takes place after the Hush murders. It is possible though that the Stalker may have survived Hush's attempt to murder him since he did survive after getting runover by a train during his first encounter with Terry.