An Immortal born in Amiens, France, he suffered his first death in 1641, when challenged to a duel of honor. He cheated, but lost anyway. He was found by Belva Silvestri, who instructed him on the ways of Immortals.
He met Alexis, an Immortal woman, and entered into an affair with her. When she left him, he was incensed. No woman had ever left him before. He pursued her, searching the countryside. When he finally found her, she was in the arms of another man. Furious, he killed the mortal lover, and when she wept for the fallen man with more emotion than she'd ever shown him, he tried for her head. She fought him, breaking his arm in the process of disarming him. When he ran, she chased him. Cornered, he begged for his life, but she took his head and quickening.
Duncan MacLeod who saw the incident, did not intervene when Alex beheaded Gerard, merely commented and rode away. LeRoi's final Watcher was Thomas Thibeault who filed the terminal report on his subject.