He was the son of an Air Force colonel, who believed Smallville was being overrun with meteor-infected people. After the second meteor shower, his father became a metahuman as well; Gabriel claimed he begged him to kill him. The inside of Gabriel's house was covered in newspaper and magazine articles and clippings detailing the effects of the meteor rocks on the town. Gabriel was the computer wizard at the Smallville Torch at Smallville High and was accepted into MIT.
However, instead of leaving the town, he followed through with his father's plan. When he had read all he needed to know about missile launching, he used his father's plan to execute the launch of a missile that would head straight for Smallville to destroy all life in the city. He overtook the control booth for a missile launching station by killing the guards on duty. He tried to warn Chloe Sullivan to save her, but she enlisted Clark's help to stop Gabriel. Clark accosted Gabriel, who shot him in the abdomen. He kidnapped Chloe and left Clark to die in the street. (Clark was later revived by his Kryptonian father Jor-El.)
Gabriel forced Chloe to witness his execution of the launch by tying her to a chair. However, she got loose and she knocked him out in an attempt to abort the launch. But Gabriel revived shortly and he and Chloe fought until Chloe managed to defeat Gabriel when she accidentally shot him with a gun and killed him.
- Gabriel is one of several humans to have driven psychotic by a hatred of meteor freaks; Van McNulty is another prominent example. Both Gabriel and Van created a plot to kill metahumans once and for all. Coincidentally, both Gabriel and Van worked at the Smallville Torch repairing computers.
- It is likely that Gabriel had a hidden crush on Chloe Sullivan, considering he cared about Chloe enough to call and warn her to escape, and personally came out to pick Chloe up when she pretended to crash her car and got stranded on the road. Despite the revelation that Chloe lied to him, Gabriel still tried to persuade the abducted Chloe to join his cause. After Chloe broke free of the restraints and knock him out temporarily, the recovered Gabriel did not simply shoot Chloe, but instead only grappled and tried to subdue her harmlessly, and was shot fatally in the struggle after Chloe attempted to seize his gun.