|Occupation|| Computer Hacker,|
White Knight of Checkmate
|Played By||Ryan McDonell|
Stuart stood up to Tess when she tried to make him wipe Lois' memories, arguing that if he messed up that he could possibly leave Lois catatonic.
Stuart first came to Tess stating that he doesn't know where the Kryptonians are but knows where they stopped in Metropolis.
Later, Tess and Stuart investigated the room in which John awoke in earlier, and saw that the people performing surgery in there were testing something and were possibly still monitoring the test subject to see if it would work. She then stated that Major Zod and his people were one step closer to getting their powers. He then showed her a familiar image they had seen before: the House of El burned into the ground, but with one difference: this Mark of El had a man lying naked in the middle.
Chloe approached him, due to his extensive computer skills, to enlist him to help her.
When Tess ordered Lois to be taken from the hospital, Stuart used some machines to show images of what she was remembering on a screen. Stuart was told to use Project Intercept for Tess to enter Lois' mind. After releasing Tess from Lois' memories of the future, Tess told Stuart to erase Lois' memories. However, Stuart stood his ground and defied her order, which he was punished with a bullet in his back. Emil and Chloe were able to get Stuart to the hospital, and treated.
Stuart spent five months in recovery after Tess had shot him. He was recruited by Checkmate and became their White Knight. He helped hack Watchtower in order to get more information that Checkmate needed on the Kandorians. He then pursued Tess who was on the run from Checkmate after betraying them. He was unable to find her and returned to base where Zod showed up, scorching the castle with his heat vision. Stuart was with Amanda Waller when Zod attacked and burned the castle to the ground. His and Waller's fate are unknown.
- Stuart was born on September 2, 1989 in Burlington, Vermont.
- He attended Phillips Exeter Academy where he graduated with honors and later attended Massachusetts Institute of Technology, B.S., M. Sc.
- He has several computing skills like: Programing in high-level languages, O.S scripting, Software Engineering, Computer System and Database Security, Secure Wireless and Wired Data Networks, Advances Algorithms, Satellite Communications, Urban/City Infrastructure Network Planning.
- Also has advance science skills like: Advanced Forensics, Chemical Engineering, Electrical, Magnetic and Optical Materials, Thermodynamics of Materials, Kinetic and Transport in Materials Engineer.
- His interests are Computer Hacking, Cryptography, Snowboarding, Skateboarding, and the Electric Guitar.
- Stuart is an MIT graduate and a "boy wonder"; and is 20 years old. (Crossfire)
- He is like a male version of Chloe Sullivan since both have the same interests and abilities.
- After he is shot by Tess Mercer, he looks like a DC Character named Jackal from the Action Comics #598.
- Campbell's prodigious hacking abilities and rivalry with Chloe makes him very similar to the Calculator, archenemy of Oracle, like Chloe and Oracle also an information broker.
- It is presumed that Stuart was murdered by Zod when he uses his heat vision at the end of the assault and Stuart is seen in the center of where Zod is blasting. And as for Waller, it is still unknown, but it's easier to presume that Stuart died.