Thomas Castillo (Earth-90: Pre-Crisis)

"Nobody is completely honest Barry! Everybody got something to hide, right?"

- Thomas Castillo to Barry Allen

Thomas Castillo was a corrupt Central City district attorney that blackmailed the Flash.

Early Life
At some point during when he was at law school, Thomas was approached by Arthur Simonson and made a deal where he could become the city's district attorney in exchange avoiding Simonsons' arrest. That arrangement was acceptable at this time.

The Fires
In 1990, when multiple mysterious fires happened around the city, Thomas was at the attorney at Simonson's trial about alleged racket and owning an illegal casino. But Simonson's lawyer mocked him to the point where he was ridiculed thus manipulating the jury to make him not guilty. At the exit of the courthouse, he had an argument with Lt. Garfield about the officers being the one to blame since they botched the testimony despite Garfield protest about how hard they tried. Thomas promised that he would take down Simonson one way or another with or without the police. Later, at Simonson's casino, he talked to Arthur about the current arrangement that he found unacceptable at the moment. He also told him that he needed to win a few cases because it's an election year. Arthur mocked him and told him that the arrangement is fine, and that he will eventually make someone took the fall to keep him as a DA. Later, Thomas met the private detective Megan Lockhart that he employed for weeks to uncover the Flash's identity. Lockhart told him that she has one possible suspect left and that she would uncover the flash's identity before Friday. When Lockhart gave away the Flash's identity, Thomas paid a visit to Barry Allen and after a grenade trick, he blackmailed Barry into meeting him for a job in 24h. When Barry showed up, Thomas give him a simple mission, winning every game in Simonson's illegal casino in order to make him lose money. After Barry manage to cause the casino to shut down for the night, Thomas visited Simonson and told him that he would have to work for him now since the Flash will make him lose all his money. The next day, Thomas went to the precinct to talk to Barry. He was disappointed to learn that the money Barry won was donated to the Riverside Park Fund. Thomas then told him that he now needs to find dirt on Paul Van Duzer tonight. That night, Thomas ordered his men to execute Dr. Tina McGee and Megan Lockhart because both of them are aware of the Flash's identity. Later again, Thomas had an argument with Simonson. Then their henchmen revealed that they have captured Lockhart recording their conversation. Lockhart kick Thomas in the stomach which made Simonson laugh before she was taken away for execution. When the Flash showed up and started to beat up everyone, Thomas secretly flew the scene and was caught by Barry. He told him that he would have to kill him which Barry is not capable of and when he tries to escape by using his car, it explodes killing him.