She was portrayed by Jane Seymour.
Genevieve ordered her son Jason Teague to start dating Lana when she learned that Lana went to Paris, France. The reason for that was because Genevieve needed Lana to show Jason the tomb where Countess Isobel was buried since Lana was Isobel's descendant. Genevieve even arranged for her old boyfriend Lionel Luthor to be free from prison to help locate the Stones of Power, something she and her husband Edward Teague were trying to find since they believed that the Stones of Power could help them find out more about the Traveler. Lana recognized Genevieve from a dream she had of Isobel being burned which made Jason believe that he was being manipulated by his mother into dating Lana which Genevieve denied.
When Jason started working for Lex Luthor after getting fired from Smallville High, Genevieve confronted Lex since she felt Lex was using Jason to get his hands on the stones and to avoid contact with Lana. Nevertheless, Genevieve was able to get Jason to help her kill Dr. Bridgette Crosby to collect the Crystal of Water.
Genevieve ordered Lionel to help her get the Crystal of Air and swore to send him back to prison if he refused. Lionel countered that by exposing Genevieve and Jason for murdering Dr. Crosby and poisoned her drink and denied the antidote unless she gave him the Crystal of Water.
Jason kidnapped Lex and Lionel, and he and Genevieve held them hostage in a cabin. The mother and son team tortured Lex to make Lionel give up the location of the Crystal of Water. Lionel tricked Genevieve into thinking he gave it to Lana and Genevieve decided to wait for Lana to come home in Lana's apartment at the Talon. Genevieve attacked Lana and Lana revealed she had the Crystal of Air in her backpack. Isobel reacted to the threat on Lana and used her body to kill Genevieve. Isobel then vanished from Lana's body and with the Mark present on her back.
- Considering that Patricia and Virgil Swan was murdered on Earth-2 by Clark Luthor, it is possible that Genevieve, her son Jason Teague, her husband Edward Teague) were also killed by Clark.
- Dr. Bridgette Crosby was originally intended to be the main antagonist in season 4.
- Genevieve and her son Jason are the main antagonists in season 4.
- Genevieve had a relationship with Lionel.
- It's hinted often by Lionel that Genevieve had an incestuous relationship with her son Jason Teague.