Nem was a member of the technologically advanced race, the Oannes.
He happened upon SG-1 in 1997, communicating with them through use of cuneiform, which Daniel recognized. When he mentioned Babylon, Nem stunned them into unconsciousness. After altering the memories of Teal'c, Colonel Jack O'Neill, and Captain Samantha Carter so that they thought Dr. Daniel Jackson was dead, to prevent them from returning, he kept Daniel imprisoned so that he would reveal the fate of Omoroca. He hoped that Daniel would willingly divulge Omoroca's fate, as he did not want to use his technology to forcibly take it, which could damage Daniel. Daniel tried to explain that the Tau'ri had freed themselves from the Goa'uld, and that Earth had lost knowledge of Babylon centuries ago, but Nem refused to believe him. Daniel then asked to Nem to use his technology to find the information he had forgotten. Though he was in terrible pain, Daniel managed to remember that Belus had killed Omoroca. Finally convinced that Daniel was telling the truth, Nem allowed him to return to his comrades, who had fought through the brainwashing and returned. In time, Nem believed that Daniel would find Sha're, and that the Tau'ri and Oannes would meet again. (SG1: "Fire and Water")