Checkmate is a covert agency under jurisdiction of the U.S. Government and an antagonist organization in the CW TV series Smallville appearing throughout the Ninth Season.
Checkmate's primary goal was to enlist metahumans and superheroes to defend the world from extraterrestrial threats. Members were identified by chess pieces that ranked their status in the organization.
In the 1970s, Checkmate had approached the Justice Society of America, demanding that they work for them and for them to unmask themselves.
When they refused, Checkmate uncovered the JSA's secret identities on their own, and then began to hunt them down with the help of the police.
When Amanda Waller became the White Queen of Checkmate, she enlisted Tess Mercer to spy on LuthorCorp CEO Lex Luthor due to his involvement with alien investigations and projects. She also began an operation that forced convicted criminals with metahuman abilities to carry out missions for them.
The ship of the alien, M'gann, crashed in Colorado, near Checkmate's Headquarters.
Amanda Waller employed Cameron Mahkent, the son of the original Icicle, as a Black Pawn. He was tasked with finding and eliminating members of the Justice Society of America. First he went after the Star Spangled Kid who he killed on a rooftop.
Then Icicle found Wesley Dodds the Sandman and killed him in his apartment. Cameron was intercepted by Doctor Fate, a mystic of the Justice Society's, and impaled him through the chest, murdering him before taking his magic helmet.
While wearing the helmet, he faced off against a combination of the Justice Society and Oliver Queen's team of heroes.
Having failed, Icicle returned to the Checkmate agency hoping to kill more JSA members, but Waller revealed that she only wanted him to bring the JSA out of retirement. She then pointed a gun in his direction and said, "Welcome to the Suicide Squad"... and fired the gun.
Checkmate then turned their sights on the one called Watchtower, who they knew was the key to accessing many metahumans like The Blur, Green Arrow, and the rest of their team. To do this, they first kidnapped Green Arrow after a successful diversion by Agent Mercer.
Bringing him onto one of their mobile bases, Waller met with Green Arrow, demanding that he accept Checkmate's invitation to join their ranks and serve his country.
Green Arrow refused and managed to escape the van. Waller hounded Tess for not making sure the prisoner was secure, telling her that failure was not an option. They realized Green Arrow's team was onto them when Detective John Jones, a Martian, managed to make his way to Checkmate headquarters at "The Castle".
Waller confronted him, telling him that the alien blood sample they had received a short time beforehand was proof of alien life (the blood sample had been given to Waller by Lois Lane from a scientist torturing Kryptonian's lab).
She trapped John with a cage of fire and left him while she had other matters to attend to. Meanwhile, Checkmate captured Watchtower, Chloe Sullivan, and brought her to "The Castle" after she had investigated Checkmate's connection to Icicle.
Clark Kent, the one called The Blur, arrived to rescue her, thanks to interrogating the location of headquarters out of Tess, when he met with Waller.
Waller demanded his and his team's loyalty, telling him that if he refused, Watchtower would die. A power outage ironically caused by Tess allowed the Blur the time to rescue Chloe and escape "The Castle".
In Amanda Waller's office, a Red Queen chess piece is on her chessboard as she states that Checkmate has been blocked by a new player and, sweeping the queen aside, saying that it's time for a new game.