Mobius is a ruthless super-villain who made his first appearance in TV episode "The A List". He is behind most of the schemes Team Knight Rider must work to prevent and is the cause of much of their pain. Mobius seems to have a personal vendetta against TKR, Kyle in particular, and takes great pleasure in teasing them and playing games with them.
Mobius had a girlfriend named Starr, an artist who paints really bad paintings (as Duke will attest to). She also seems to despise TKR almost as much as Mobius himself. She had her own personal manservant, Roland, who is a huge man with about 90% muscle over his body. He speaks in short sentences and sems to have a somewhat slow mind, and is very protectful of Starr, even though she treats him poorly.
Not a lot is known about who Mobius really is. It was hinted in the TV series that he might be Kyle's father, who was an ex-CIA operative turned traitor. Mobius himself seems to be suffering from a disease that is slowly rotting his body, confining him to a powered-up wheelchair and making him speak through tubes. He gets around pretty slick for a guy in a wheelchair, even managed to board SkyOne.
In the new season, we see Mobius again in the last chapter, "Friend and Foe", where he admits his alter ego as Chaser, a man Kyle's younger brother has been after for years now and whom TKR has been unknowingly battling throughout all of season 02. Mobius tells them all he is actually Kyle's father, Charles Stewart, and they are inclined to believe him since he resembles the ex-CIA agent and knows all about Kyle's past.
**WARNING!! FOLLOWING INFORMATION CONTAINS SPOILERS FOR SEASON 03!!**
Unfortunately, we see the end of Mobius as he and Starr are both killed in season 03 "Day of Doom Pt. Two", along with KITT. However, as the new series progresses, new mysteries and revelations are uncovered about Kyle's father that make TKR doubt Mobius' earlier paternal claims.