Year's ago, after Jeff Palmer's long and difficult rehabilitation at Belle Reve Sanitarium, Jeff was invited by his sister Amy to join a government organization that worked closely with Luthorcorp. Amy Palmer was still utterly obsessed with Lex Luthor and believed that Jeff could turn his life around with Luthorcorp.
One day Jeff was sent on a mission by his boss Tina Greer to arrest a convicted murderer. Jeff tracked down this person of interest. Having been told by Tina that this person wouldn't offer much resistance Jeff approached this man, and told him that he had been ordered to take him into custody. The man offered no resistance. As Jeff reached to put handcuffs on him this man pulled out a knife and stabbed him. The two of them struggled. Jeff reacted instinctively, and in a matter of seconds the man lay dying on the floor.
Jeff was told by this person that Jeff had been set up. Jeff learned that there was no "murderer" as he had been told by Tina. He also learned that he had been made to believe he was a government agent when in fact he was actually working for a secret criminal organization under the direct control of Lex Luthor.
Jeff confronted Tina with this information. He yelled at her, expecting that he would be fired. Tina instead knocked him on the floor, and told him that if he ever left her he would be killed.
Tina despised Jeff for his disobedience, but needed his unique ability. (Over the years Jeff had become meteor-infected by the very substance he used to turn himself invisible. Eventually he was able to make himself invisible with a thought.)
Jeff reluctantly served in Lex Luthor's secret task force. He was very depressed in his isolation. He came to believe that if he talked to his sister she would also be in danger. Jeff spent most of his time with Tina, and one other agent known to him only as 'Bizarro'.
The Bizarro that Jeff knew was very egotistical. Bizarro had been captured a year before by Lex Luthor's operatives, Molly Griggs and Dr. Helen Bryce, and was controlled by Tina using a device that controlled the amount of blue kryptonite in his bloodstream. Tina subsequently used this device to punish Bizarro for his arrogance.
However Bizarro eventually came to admire his commander Tina Greer for her bravery, her ingenuity, and her relentlessness. His change of heart soon made him one of Tina's most valuable agents and, like Tina, he also despised Jeff for his disobedience.
Eventually, Bizarro fell in love with Star Sapphire. He began to regret his arrogance, his cruelty, and his entire role in the Legion.
But Tina recognized Bizarro's change in behavior. She used drugs to extend her control over him and Star Sapphire.
After the fight between Tina Greer and Jeff at Belle Reve Sanitarium Jeff Palmer disappeared. Some say that Jeff died that day. Others say that Jeff worked in secret, aiding the Justice League. Some others say that Jeff Palmer was driven to the brink of madness that day by Tina, and spends his nights plotting his ultimate revenge against the Legion of Doom.