- "If you want to play God, you might want to remember his greatest gift. Free will. - Grant Gabriel (Gemini)
As a clone of Julian Luthor, Grant has exactly the same appearance as Julian as he would have been in his early 20's. Grant has brown hair and eyes. He often wears a blue or black suit with a white shirt and a tie.
Julian Luthor died in infancy when Lex Luthor was twelve. Grant was cloned from Julian's DNA, and implanted with false memories of a childhood which detailed how he was given up for adoption, so that he would believe himself to be Lex's brother.
He remembered being the former editor of the Star City Post (It's unknown if he was actually an editor or if the memory was implanted).
Grant Gabriel introduced himself to Chloe Sullivan and Lois Lane on his first day at the Daily Planet. He seemed to know a lot about Chloe, but was unimpressed with her journalistic work. Instead, he was intrigued by the tenacity of her cousin Lois. He offered Lois Lane a job at the Planet if she could write a good story about her discovery of a mysterious spacecraft, thinking it would increase circulation. However, even though she could provide no evidence of the ship's existence, Grant still gave Lois the job at Daily Planet, giving her the desk right next to Chloe. Grant was under the impression that Chloe's journalistic spark had burned out, but that Lois was on the fast-track to becoming a brilliant journalist. He assigned Lois exclusive stories in New York City and Los Angeles, but had yet to actually publish any of Lois's stories.
When a local beauty queen was frozen to death, he sent Chloe and Jimmy Olsen to report it. When popular actress Rachel Davenport was almost killed on her movie set, Grant was furious that the Smallville Ledger received an exclusive story. He sent Lois to cover the event, even though she felt that LuthorCorp's purchase of land near Reeves Dam was more important. However, Rachel agreed to give a rare interview to Chloe as a favor to Clark Kent.
Although the land purchase article was killed by Grant, it turned out that Lois had been right: Lana Lang had bought the land to imprison Lionel Luthor. That story never came to light though, possibly because Grant continually stymied Lois's attempts to investigate the Luthors. When Lana later presented Grant with a hard drive containing details on Lex Luthor's Project Scion, Grant refused to use stolen evidence to expose the project. He was later seen deleting the files from the hard drive.
Lois did not know of Grant's relationship with his brother Lex. Lex had been taking care of Grant for quite a while without their father knowing about it. Lex told Grant to cut off his relationship with Lois. Grant claimed they broke it off while in reality they were still dating.
Grant found out about his origins when he met Adrian Cross, a failed clone experiment who had the same DNA and memories as Grant. He discovered they were both clones of Julian Luthor, and became outraged at Lex for being nothing more than an experiment. He became even more upset when he learned that Lex had just bought the Daily Planet and become his boss. Later, Grant broke up with Lois, convinced that their relationship had become too complicated.
When Grant went to Lionel to expose himself, Grant was welcomed with open arms by his "father", much to his surprise. Afterwards, Lionel told Lex of his meeting with Gabriel. Lionel compared Lex to Gabriel with Lex coming up far short. Later, Lex fired Grant from his post as editor of the Daily Planet for disobeying him, and out of jealousy towards Grant. Grant was warned by Lex to stay away from Lionel, but Grant wanted to face this head on and proceeded to start building a relationship with his "father". After one final warning to Grant to stay away from Lionel, Lex felt that he was forced to do something about it. He had an assassin posing as a mugger kill Grant as Grant and Lionel were leaving a steak dinner they had together. "Julian" died in Lionel's arms.
- Season Seven:
- Grant Gabriel is the only major recurring character that never met Clark.
- Grant Gabriel (G.G.) had the reoccurring consonants as initials, just like his father, brother and mother (L.L.).
- Grant Gabriel appeared in 7 episodes, which tied him in number of appearances with Dr. Harden, Adam Knight, Gina, Jeff Hage, and Faora (clone) as the 10th most frequently seen recurring characters in the series after Jor-El, Nancy Adams, Brainiac, Emil Hamilton, Ethan Miller, John Jones, Nell Potter, George, and Helen Bryce. Grant, Dr. Harden, Adam, Gina, Jeff, and Faora are the most frequently seen recurring characters in the series who are tied with each other in the number of episodes they appeared in.
- Michael Cassidy (Grant) also played the part of Zack Stevens in The O.C. He is the last of five O.C. alumni to appear on Smallville. The first was Adam Brody (Justin Gaines) and the second was Chris Carmack (Geoff Johns), followed by Johnny Lewis (Gabriel Duncan) and Paul Wesley (Lucas Luthor).
- Michael Cassidy portrayed a undercover CIA agent credited as Jimmy Olsen in Batman v Superman: Dawn of Justice. Cassidy is one of numerous actors (including Amy Adams, Alessandro Juliani, Adam Brody, and Ted Whitall) appearing in both the universes of Smallville and the cinematic DC Extended universe.