Little is known about the Linear Man's origin and background. He comes from an unknown point and time in the future. When he first appears, he is upset about Booster Gold, seeing him misusing time travel for selfish purposes, and wants to bring Booster Gold back to his own time and era in the 25th Century.
The Linear Man manipulates Booster's robot assistant Skeets to lure Booster Gold to Metropolis. While he's trying to capture Booster Gold, Superman intervenes and is drawn into the time-stream instead of Booster Gold. A journey and battle between Superman and the Linear Man through time and space is the consequence.
The Linear Man was created by writer Dan Jurgens and first appeared in DC's story arc Superman: Time and Time Again starting with Adventures of Superman #476. The story arc was published in 1991.
Powers and Abilities
Though he has no super powers, the Linear Man possesses some powerful time-travel devices that can send him and other persons through time and space. He is wearing an instrument around his wrist with which he can open a vortex in space-time that can swallow persons and objects.