- Real Name: Thaal Sinestro
- Alias: Green Lantern, White Lantern
- Identity: Public Identity
- Alignment: Neutral
- Gender: Male
- Hair: Black, Eyes: Amber
- Occupation: Green Lantern
- First appearance: Green Lantern Vol 2 #7 (August, 1961)
Thaal Sinestro of Korugar is the arch-nemesis of Green Lantern. At one point the greatest member of the Green Lantern Corps, he was corrupted by his power and exiled for crimes against his own people. He now seeks to impose his own order and control onto the universe, employing a yellow power ring to combat the green he has grown to despise. His prowess and ruthlessness have made him one of the most feared villains in existence, and eventually he establishes his own Sinestro Corps.
Green Lantern Corps
Sinestro was selected by the Guardians of the Universe to become a member of the Green Lantern Corps for his honor and fearlessness. At his height, he was considered to be the greatest of all the Green Lanterns, and Sector 1417 was almost entirely devoid of crime and lawlessness under his vigilant protection. The Guardians had never erred in their judgment before, and he would later be considered one of their greatest mistakes. His prowess
was so great that he was assigned as a mentor to a number of rookie lanterns showing similar promise...the greatest of which would be his last student, Hal Jordan. Ganthet had specifically requested that the two train together, and they quickly became great friends.
Throughout his time in the Corps, Abin Sur was Thaal Sinestro's best friend and trusted confidante, so much so that they considered each other to be brothers. He would eventually fall in love with and marry Arin Sur, his friend's sister, and the two would have a child together. Abin confided in Sinestro what he had learned of the Blackest Night, where a darkness would rise to destroy all life, something Sinestro dismissed as lies by the Five Inversions who told Abin the prophecy. Eventually Abin was killed by the monster known as Atrocitus. Sinestro would later bring Atrocitus to justice for Abin's murder with the help of Abin's successer, Hal Jordan. After Sinestro dropped him off at the prison world of Ysmault, Atrocitus taunts Sinestro with a prophecy of the chaos and deadly coup that would lead to Sinestro's fall from grace. However, Sinestro ignores him and leaves. However, as he became increasingly stressed with keeping his sector as perfect and as ordered as he needed it to be, Sinestro slowly became more unhinged and started employing more questionable tactics in his behavior. His actions were unwelcome by the Korugarans, and threats were made against his family. Arin recognized the danger posed by Sinestro's methods, and secretly gave their daughter away. Sinestro would be unable to find his daughter, and Arin soon died through unknown circumstances.
Dictator of Korugar
On their first diplomatic assignment, Hal proved to be reckless and Sinestro believed that he was a waste of his time. Then upon returning to his home planet of Korugar, they were met with very much opposition and Hal discovered that Sinestro forced his planet to worship him and that he had a very strict and unjust set of rules. After being gone so long, Korugar's citizens rebelled and Sinestro lost control. After a short battle, Hal knocked some sense into Sinestro and he realized that he must hide for the Guardians will punish both of them. After hiding in one of Earth's prisons with Hal Jordan, Oan manhunters brought him in to Oa and he was tried. After Hal testified against him, Sinestro swore revenge against Hal and the Corps right before he was banished to Qward in the Antimatter Universe. There, he met the Weaponers of Qward, who helped him forge a yellow power ring to counter the Green Lantern Corps.