|Out of universe information|
- "My name is Joe Spencer, and you ruined my life!"
- —Joe to Jack O'Neill
Joe was unable to create or tell amusing jokes or stories of his own, but began to tell of the visions of SG-1 he sees as if they were stories he had conjured out of thin air. To start with, he told these visions to his son and the customers in his barbershop, entertaining them where he had previously been nothing but a bore. Later, at the suggestion of his wife, he started to write them down and send them in to various magazines (all of which reject them) instead of telling each and every individual the tiniest of details relating to SG-1. He also knew about Brigadier General Jack O'Neill's feelings toward Lt. Colonel Samantha Carter, which he promised not to tell anyone.
Eventually, the people he told started to get tired of his tales of SG-1 and, eventually, they stopped coming to his barbershop. Despite his wife's urging, telling him to stop writing the episodes down, he continued to type and becomes convinced that the visions are actually happening. After years of too-intense focus on SG-1, long since passed into obsession, his wife left with their son. At that point he tried to find evidence that what he was seeing is real, collecting data on mysterious stellar phenomenon and unexplained deaths, but is unable to contact O'Neill.
Eventually, he tracked down where O'Neill lives, who helped him start to piece his life back together by personally talking to his wife. They discover that the reason he had been seeing the visions, flashes of the life of O'Neill, is because of an Ancient Long-range communication stone brought back from P3R-233, the same world as the Quantum Mirror. The device, which was activated by O'Neill when he touched a mysterious black stone in Dr. Daniel Jackson's lab, connects two minds together telepathically and Joe, who possessed the same Ancient gene as O'Neill, activated the companion device when he touched the stone at the garage sale. He took O'Neill to see his wife who wanted to divorce him and O'Neill revealed the truth to her, presumably saving his marriage. (SG1: "There But for the Grace of God", "Citizen Joe")
- Dan Castellaneta who plays Joe is best known for playing Homer Simpson on the Simpsons, a show that Richard Dean Anderson (Jack O'Neill) is a fan of.