As an archeologist, Grayson visited various worlds. At every dig he would have a stockpile of alcohol to help him get through the work. It seemed to pay off as the dig always finished before the stockpile did. In 2493 he met fellow archeologist Jake Ramsey on the world of Melkora. While initially hostile, he nonetheless joined Ramsey's archeological team. In 2501, Grayson began his second last dig on the hostile world of Gelgaris alongside thirty other archaeologists and "one originally perky and now sullen intern."
After two hard years, Grayson took part in Ramsey's last expedition, sponsored by Valerian Mengsk, to the airless world of Nemaka. They were there to excavate a strange artifact-one that had stumped and unnerved previous expeditions. Grayson and co. were no exception and he took to drinking to avoid the "spookiness" of the artifact.
Eventually Ramsey gained entry to the artifact, albeit at the cost of being rendered unconscious by an unknown being. Aid from the Dominion was requested and while granted, it involved the archeologists being taken prisoner and placed in cells aboard the Gray Tiger. This ultimately led to their deaths when a crazed marine disabled the ship's life support systems.