Archaeologist and curator of the Megakat City Museum of History, Dr. Abby Sinian is the foremost expert on the supernatural in Megakat City. She has come into conflict with the Pastmaster on at least two occasions; first, when she and Callie Briggs just happened to be in his way when he broke into the museum searching for the Tome of Time, and again when he resurrected the Mummies of Katchu Pitchu.
During the former event, Dr. Sinian was instrumental in pointing out that the Tome of Time was the source of the majority of the Pastmaster's powers, a fact largely ignored by Commander Feral. In the second, she and Henson were endangered by the giant mummies, but rescued by the Swat Kats and Cybertron, and Sinian told the vigilantes to destroy the Headdress of Power in order to put an end to the mummies.
In-between her encounters with the Pastmaster, Dr. Sinian also proved quite helpful when the ghost of the Red Lynx came back from the dead and tried to kill Mayor Manx. Without her, the Swat Kats would've never learned that only a member of the Manx family could destroy the Red Lynx for good again.
- Dr. Sinian would've appeared a fourth time in the episode Succubus! (also known as The Curse of Kataluna), had the show not been cancelled. Here, she would've told Callie Briggs and Felina Feral about the legend of the evil succubus, before being attacked along with them by Katrina Moorkroft's pet three-headed monster.